diff --git a/taiga/base/filters.py b/taiga/base/filters.py
index 5c73ed95..1cc73a60 100644
--- a/taiga/base/filters.py
+++ b/taiga/base/filters.py
@@ -17,15 +17,13 @@ import operator
 from functools import reduce
 import logging
 
+from django.apps import apps
 from django.db.models import Q
-from django.db.models.sql.where import ExtraWhere, OR, AND
 
 from rest_framework import filters
 
-from taiga.base import tags
 from taiga.base import exceptions as exc
 
-from taiga.projects.models import Membership
 
 logger = logging.getLogger(__name__)
 
@@ -101,7 +99,8 @@ class PermissionBasedFilterBackend(FilterBackend):
             try:
                 project_id = int(request.QUERY_PARAMS["project"])
             except:
-                logger.error("Filtering project diferent value than an integer: {}".format(request.QUERY_PARAMS["project"]))
+                logger.error("Filtering project diferent value than an integer: {}".format(
+                                                           request.QUERY_PARAMS["project"]))
                 raise exc.BadRequest("'project' must be an integer value.")
 
         qs = queryset
@@ -109,7 +108,8 @@ class PermissionBasedFilterBackend(FilterBackend):
         if request.user.is_authenticated() and request.user.is_superuser:
             qs = qs
         elif request.user.is_authenticated():
-            memberships_qs = Membership.objects.filter(user=request.user)
+            membership_model = apps.get_model('projects', 'Membership')
+            memberships_qs = membership_model.objects.filter(user=request.user)
             if project_id:
                 memberships_qs = memberships_qs.filter(project_id=project_id)
             memberships_qs = memberships_qs.filter(Q(role__permissions__contains=[self.permission]) |
@@ -187,7 +187,8 @@ class CanViewProjectObjFilterBackend(FilterBackend):
             try:
                 project_id = int(request.QUERY_PARAMS["project"])
             except:
-                logger.error("Filtering project diferent value than an integer: {}".format(request.QUERY_PARAMS["project"]))
+                logger.error("Filtering project diferent value than an integer: {}".format(
+                                                           request.QUERY_PARAMS["project"]))
                 raise exc.BadRequest("'project' must be an integer value.")
 
         qs = queryset
@@ -195,7 +196,8 @@ class CanViewProjectObjFilterBackend(FilterBackend):
         if request.user.is_authenticated() and request.user.is_superuser:
             qs = qs
         elif request.user.is_authenticated():
-            memberships_qs = Membership.objects.filter(user=request.user)
+            membership_model = apps.get_model("projects", "Membership")
+            memberships_qs = membership_model.objects.filter(user=request.user)
             if project_id:
                 memberships_qs = memberships_qs.filter(project_id=project_id)
             memberships_qs = memberships_qs.filter(Q(role__permissions__contains=['view_project']) |
@@ -203,7 +205,8 @@ class CanViewProjectObjFilterBackend(FilterBackend):
 
             projects_list = [membership.project_id for membership in memberships_qs]
 
-            qs = qs.filter(Q(id__in=projects_list) | Q(public_permissions__contains=["view_project"]))
+            qs = qs.filter((Q(id__in=projects_list) |
+                            Q(public_permissions__contains=["view_project"])))
         else:
             qs = qs.filter(public_permissions__contains=["view_project"])
 
@@ -221,6 +224,25 @@ class IsProjectMemberFilterBackend(FilterBackend):
 
         return super().filter_queryset(request, queryset.distinct(), view)
 
+
+class MembersFilterBackend(filters.BaseFilterBackend):
+    def filter_queryset(self, request, queryset, view):
+        project_id = request.QUERY_PARAMS.get('project', None)
+        if project_id:
+            project_model = apps.get_model('projects', 'Project')
+            project = get_object_or_404(project_model, pk=project_id)
+            if (request.user.is_authenticated() and
+                    project.memberships.filter(user=request.user).exists()):
+                return queryset.filter(memberships__project=project).distinct()
+            else:
+                raise exc.PermissionDenied(_("You don't have permisions to see this project users."))
+
+        if request.user.is_superuser:
+            return queryset
+
+        return []
+
+
 class BaseIsProjectAdminFilterBackend(object):
     def get_project_ids(self, request, view):
         project_id = None
@@ -233,7 +255,8 @@ class BaseIsProjectAdminFilterBackend(object):
         if not request.user.is_authenticated():
             return []
 
-        memberships_qs = Membership.objects.filter(user=request.user, is_owner=True)
+        membership_model = apps.get_model('projects', 'Membership')
+        memberships_qs = membership_model.objects.filter(user=request.user, is_owner=True)
         if project_id:
             memberships_qs = memberships_qs.filter(project_id=project_id)
 
diff --git a/taiga/projects/api.py b/taiga/projects/api.py
index 406438a7..f9f605a5 100644
--- a/taiga/projects/api.py
+++ b/taiga/projects/api.py
@@ -20,7 +20,8 @@ from django.db.models import signals
 from django.core.exceptions import ValidationError
 from django.utils.translation import ugettext_lazy as _
 
-from taiga.base import filters, response
+from taiga.base import filters
+from taiga.base import response
 from taiga.base import exceptions as exc
 from taiga.base.decorators import list_route
 from taiga.base.decorators import detail_route
@@ -32,7 +33,6 @@ from taiga.base.utils.slug import slugify_uniquely
 from taiga.projects.mixins.ordering import BulkUpdateOrderMixin
 from taiga.projects.mixins.on_destroy import MoveOnDestroyMixin
 
-from taiga.users.models import Role
 from taiga.projects.userstories.models import UserStory
 from taiga.projects.tasks.models import Task
 from taiga.projects.issues.models import Issue
@@ -325,7 +325,7 @@ class ProjectTemplateViewSet(ModelCrudViewSet):
 
 
 ######################################################
-## Members Invitations and Roles
+## Members & Invitations
 ######################################################
 
 class MembershipViewSet(ModelCrudViewSet):
@@ -403,20 +403,3 @@ class InvitationViewSet(ModelListViewSet):
 
     def list(self, *args, **kwargs):
         raise exc.PermissionDenied(_("You don't have permisions to see that."))
-
-
-class RolesViewSet(ModelCrudViewSet):
-    model = Role
-    serializer_class = serializers.RoleSerializer
-    permission_classes = (permissions.RolesPermission, )
-    filter_backends = (filters.CanViewProjectFilterBackend,)
-    filter_fields = ('project',)
-
-    def pre_delete(self, obj):
-        move_to = self.request.QUERY_PARAMS.get('moveTo', None)
-        if move_to:
-            role_dest = get_object_or_404(self.model, project=obj.project, id=move_to)
-            qs = models.Membership.objects.filter(project_id=obj.project.pk, role=obj)
-            qs.update(role=role_dest)
-
-        super().pre_delete(obj)
diff --git a/taiga/projects/permissions.py b/taiga/projects/permissions.py
index 4d0fcdbd..5fa9180b 100644
--- a/taiga/projects/permissions.py
+++ b/taiga/projects/permissions.py
@@ -16,9 +16,13 @@
 
 from django.utils.translation import ugettext_lazy as _
 
-from taiga.base.api.permissions import (TaigaResourcePermission, HasProjectPerm,
-                                        IsAuthenticated, IsProjectOwner,
-                                        AllowAny, IsSuperUser, PermissionComponent)
+from taiga.base.api.permissions import TaigaResourcePermission
+from taiga.base.api.permissions import HasProjectPerm
+from taiga.base.api.permissions import IsAuthenticated
+from taiga.base.api.permissions import IsProjectOwner
+from taiga.base.api.permissions import AllowAny
+from taiga.base.api.permissions import IsSuperUser
+from taiga.base.api.permissions import PermissionComponent
 
 from taiga.base import exceptions as exc
 from taiga.projects.models import Membership
@@ -32,8 +36,8 @@ class CanLeaveProject(PermissionComponent):
 
         try:
             if not services.can_user_leave_project(request.user, obj):
-                raise exc.PermissionDenied(_("You can't leave the project if there are no more owners"))
-
+                raise exc.PermissionDenied(_("You can't leave the project if there are no "
+                                             "more owners"))
             return True
         except Membership.DoesNotExist:
             return False
@@ -140,14 +144,6 @@ class IssueTypePermission(TaigaResourcePermission):
     bulk_update_order_perms = IsProjectOwner()
 
 
-class RolesPermission(TaigaResourcePermission):
-    retrieve_perms = HasProjectPerm('view_project')
-    create_perms = IsProjectOwner()
-    update_perms = IsProjectOwner()
-    destroy_perms = IsProjectOwner()
-    list_perms = AllowAny()
-
-
 # Project Templates
 
 class ProjectTemplatePermission(TaigaResourcePermission):
diff --git a/taiga/projects/serializers.py b/taiga/projects/serializers.py
index 5c89484f..ad0e99a7 100644
--- a/taiga/projects/serializers.py
+++ b/taiga/projects/serializers.py
@@ -14,27 +14,32 @@
 # You should have received a copy of the GNU Affero General Public License
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
-from os import path
 
 from django.utils.translation import ugettext_lazy as _
 from django.db.models import Q
 
 from rest_framework import serializers
 
-from taiga.base.serializers import JsonField, PgArrayField, ModelSerializer, TagsColorsField
-from taiga.users.models import Role, User
+from taiga.base.serializers import JsonField
+from taiga.base.serializers import PgArrayField
+from taiga.base.serializers import ModelSerializer
+from taiga.base.serializers import TagsColorsField
 from taiga.users.services import get_photo_or_gravatar_url
 from taiga.users.serializers import UserSerializer
+from taiga.users.serializers import ProjectRoleSerializer
 from taiga.users.validators import RoleExistsValidator
 
-from taiga.permissions.service import get_user_project_permissions, is_project_owner
+from taiga.permissions.service import get_user_project_permissions
+from taiga.permissions.service import is_project_owner
 
 from . import models
 from . import services
 from . validators import ProjectExistsValidator
 
 
-# User Stories common serializers
+######################################################
+## Custom values for selectors
+######################################################
 
 class PointsSerializer(ModelSerializer):
     class Meta:
@@ -69,10 +74,12 @@ class UserStoryStatusSerializer(ModelSerializer):
         qs = None
         # If the user story status exists:
         if self.object and attrs.get("name", None):
-            qs = models.UserStoryStatus.objects.filter(project=self.object.project, name=attrs[source])
+            qs = models.UserStoryStatus.objects.filter(project=self.object.project,
+                                                       name=attrs[source])
 
         if not self.object and attrs.get("project", None)  and attrs.get("name", None):
-            qs = models.UserStoryStatus.objects.filter(project=attrs["project"], name=attrs[source])
+            qs = models.UserStoryStatus.objects.filter(project=attrs["project"],
+                                                       name=attrs[source])
 
         if qs and qs.exists():
               raise serializers.ValidationError("Name duplicated for the project")
@@ -80,8 +87,6 @@ class UserStoryStatusSerializer(ModelSerializer):
         return attrs
 
 
-# Task common serializers
-
 class TaskStatusSerializer(ModelSerializer):
     class Meta:
         model = models.TaskStatus
@@ -103,7 +108,6 @@ class TaskStatusSerializer(ModelSerializer):
 
         return attrs
 
-# Issues common serializers
 
 class SeveritySerializer(ModelSerializer):
     class Meta:
@@ -142,13 +146,16 @@ class IssueTypeSerializer(ModelSerializer):
         model = models.IssueType
 
 
-# Projects
+######################################################
+## Members
+######################################################
 
 class MembershipSerializer(ModelSerializer):
     role_name = serializers.CharField(source='role.name', required=False, read_only=True)
     full_name = serializers.CharField(source='user.get_full_name', required=False, read_only=True)
     user_email = serializers.EmailField(source='user.email', required=False, read_only=True)
-    is_user_active = serializers.BooleanField(source='user.is_active', required=False, read_only=True)
+    is_user_active = serializers.BooleanField(source='user.is_active', required=False,
+                                              read_only=True)
     email = serializers.EmailField(required=True)
     color = serializers.CharField(source='user.color', required=False, read_only=True)
     photo = serializers.SerializerMethodField("get_photo")
@@ -210,7 +217,8 @@ class MembershipSerializer(ModelSerializer):
         if project is None:
             project = self.object.project
 
-        if self.object and not services.project_has_valid_owners(project, exclude_user=self.object.user):
+        if (self.object and
+                not services.project_has_valid_owners(project, exclude_user=self.object.user)):
             raise serializers.ValidationError(_("At least one of the user must be an active admin"))
 
         return attrs
@@ -229,6 +237,21 @@ class ProjectMembershipSerializer(ModelSerializer):
         return get_photo_or_gravatar_url(project.user)
 
 
+class MemberBulkSerializer(RoleExistsValidator, serializers.Serializer):
+    email = serializers.EmailField()
+    role_id = serializers.IntegerField()
+
+
+class MembersBulkSerializer(ProjectExistsValidator, serializers.Serializer):
+    project_id = serializers.IntegerField()
+    bulk_memberships = MemberBulkSerializer(many=True)
+    invitation_extra_text = serializers.CharField(required=False, max_length=255)
+
+
+######################################################
+## Projects
+######################################################
+
 class ProjectSerializer(ModelSerializer):
     tags = PgArrayField(required=False)
     anon_permissions = PgArrayField(required=False)
@@ -300,23 +323,20 @@ class ProjectDetailSerializer(ProjectSerializer):
         return serializer.data
 
 
-class ProjectRoleSerializer(ModelSerializer):
+######################################################
+## Starred
+######################################################
+
+class StarredSerializer(ModelSerializer):
     class Meta:
-        model = Role
-        fields = ('id', 'name', 'slug', 'order', 'computable')
+        model = models.Project
+        fields = ['id', 'name', 'slug']
 
 
-class RoleSerializer(ModelSerializer):
-    members_count = serializers.SerializerMethodField("get_members_count")
-    permissions = PgArrayField(required=False)
-
-    class Meta:
-        model = Role
-        fields = ('id', 'name', 'permissions', 'computable', 'project', 'order', 'members_count')
-
-    def get_members_count(self, obj):
-        return obj.memberships.count()
 
+######################################################
+## Project Templates
+######################################################
 
 class ProjectTemplateSerializer(ModelSerializer):
     default_options = JsonField(required=False, label=_("Default options"))
@@ -332,20 +352,3 @@ class ProjectTemplateSerializer(ModelSerializer):
     class Meta:
         model = models.ProjectTemplate
         read_only_fields = ("created_date", "modified_date")
-
-
-class StarredSerializer(ModelSerializer):
-    class Meta:
-        model = models.Project
-        fields = ['id', 'name', 'slug']
-
-
-class MemberBulkSerializer(RoleExistsValidator, serializers.Serializer):
-    email = serializers.EmailField()
-    role_id = serializers.IntegerField()
-
-
-class MembersBulkSerializer(ProjectExistsValidator, serializers.Serializer):
-    project_id = serializers.IntegerField()
-    bulk_memberships = MemberBulkSerializer(many=True)
-    invitation_extra_text = serializers.CharField(required=False, max_length=255)
diff --git a/taiga/routers.py b/taiga/routers.py
index 7ca20aa6..ad39b94c 100644
--- a/taiga/routers.py
+++ b/taiga/routers.py
@@ -18,15 +18,18 @@ from taiga.base import routers
 
 router = routers.DefaultRouter(trailing_slash=False)
 
-# taiga.users
-from taiga.users.api import UsersViewSet
+
+# Users & Roles
 from taiga.auth.api import AuthViewSet
+from taiga.users.api import UsersViewSet
+from taiga.users.api import RolesViewSet
 
-router.register(r"users", UsersViewSet, base_name="users")
 router.register(r"auth", AuthViewSet, base_name="auth")
+router.register(r"users", UsersViewSet, base_name="users")
+router.register(r"roles", RolesViewSet, base_name="roles")
 
 
-#taiga.userstorage
+# User Storage
 from taiga.userstorage.api import StorageEntriesViewSet
 
 router.register(r"user-storage", StorageEntriesViewSet, base_name="user-storage")
@@ -51,8 +54,7 @@ router.register(r"importer", ProjectImporterViewSet, base_name="importer")
 router.register(r"exporter", ProjectExporterViewSet, base_name="exporter")
 
 
-# Projects & Types
-from taiga.projects.api import RolesViewSet
+# Projects & Selectors
 from taiga.projects.api import ProjectViewSet
 from taiga.projects.api import MembershipViewSet
 from taiga.projects.api import InvitationViewSet
@@ -65,8 +67,6 @@ from taiga.projects.api import PriorityViewSet
 from taiga.projects.api import SeverityViewSet
 from taiga.projects.api import ProjectTemplateViewSet
 
-
-router.register(r"roles", RolesViewSet, base_name="roles")
 router.register(r"projects", ProjectViewSet, base_name="projects")
 router.register(r"project-templates", ProjectTemplateViewSet, base_name="project-templates")
 router.register(r"memberships", MembershipViewSet, base_name="memberships")
@@ -79,22 +79,27 @@ router.register(r"issue-types", IssueTypeViewSet, base_name="issue-types")
 router.register(r"priorities", PriorityViewSet, base_name="priorities")
 router.register(r"severities",SeverityViewSet , base_name="severities")
 
+
 # Attachments
 from taiga.projects.attachments.api import UserStoryAttachmentViewSet
 from taiga.projects.attachments.api import IssueAttachmentViewSet
 from taiga.projects.attachments.api import TaskAttachmentViewSet
 from taiga.projects.attachments.api import WikiAttachmentViewSet
 
-router.register(r"userstories/attachments", UserStoryAttachmentViewSet, base_name="userstory-attachments")
+router.register(r"userstories/attachments", UserStoryAttachmentViewSet,
+                base_name="userstory-attachments")
 router.register(r"tasks/attachments", TaskAttachmentViewSet, base_name="task-attachments")
 router.register(r"issues/attachments", IssueAttachmentViewSet, base_name="issue-attachments")
 router.register(r"wiki/attachments", WikiAttachmentViewSet, base_name="wiki-attachments")
 
+
 # Webhooks
 from taiga.webhooks.api import WebhookViewSet, WebhookLogViewSet
+
 router.register(r"webhooks", WebhookViewSet, base_name="webhooks")
 router.register(r"webhooklogs", WebhookLogViewSet, base_name="webhooklogs")
 
+
 # History & Components
 from taiga.projects.history.api import UserStoryHistory
 from taiga.projects.history.api import TaskHistory
@@ -131,22 +136,30 @@ router.register(r"issues/(?P<issue_id>\d+)/voters", VotersViewSet, base_name="is
 router.register(r"wiki", WikiViewSet, base_name="wiki")
 router.register(r"wiki-links", WikiLinkViewSet, base_name="wiki-links")
 
+
 # Notify policies
 from taiga.projects.notifications.api import NotifyPolicyViewSet
 
 router.register(r"notify-policies", NotifyPolicyViewSet, base_name="notifications")
 
+
 # GitHub webhooks
 from taiga.hooks.github.api import GitHubViewSet
+
 router.register(r"github-hook", GitHubViewSet, base_name="github-hook")
 
+
 # Gitlab webhooks
 from taiga.hooks.gitlab.api import GitLabViewSet
+
 router.register(r"gitlab-hook", GitLabViewSet, base_name="gitlab-hook")
 
+
 # Bitbucket webhooks
 from taiga.hooks.bitbucket.api import BitBucketViewSet
+
 router.register(r"bitbucket-hook", BitBucketViewSet, base_name="bitbucket-hook")
 
+
 # feedback
 #   - see taiga.feedback.routers and taiga.feedback.apps
diff --git a/taiga/users/api.py b/taiga/users/api.py
index b634a962..a446de8d 100644
--- a/taiga/users/api.py
+++ b/taiga/users/api.py
@@ -26,20 +26,21 @@ from django.conf import settings
 from easy_thumbnails.source_generators import pil_image
 
 from rest_framework.response import Response
-from rest_framework.filters import BaseFilterBackend
 from rest_framework import status
 
-from djmail.template_mail import MagicMailBuilder, InlineCSSTemplateMail
+from djmail.template_mail import MagicMailBuilder
+from djmail.template_mail import InlineCSSTemplateMail
 
 from taiga.auth.tokens import get_user_for_token
-from taiga.base.decorators import list_route, detail_route
+from taiga.base.decorators import list_route
+from taiga.base.decorators import detail_route
 from taiga.base import exceptions as exc
+from taiga.base import filters
 from taiga.base.api import ModelCrudViewSet
 from taiga.base.api.utils import get_object_or_404
-from taiga.base.utils.slug import slugify_uniquely
+from taiga.base.filters import MembersFilterBackend
 from taiga.projects.votes import services as votes_service
 from taiga.projects.serializers import StarredSerializer
-from taiga.permissions.service import is_project_owner
 
 from . import models
 from . import serializers
@@ -47,22 +48,9 @@ from . import permissions
 from .signals import user_cancel_account as user_cancel_account_signal
 
 
-class MembersFilterBackend(BaseFilterBackend):
-    def filter_queryset(self, request, queryset, view):
-        project_id = request.QUERY_PARAMS.get('project', None)
-        if project_id:
-            Project = apps.get_model('projects', 'Project')
-            project = get_object_or_404(Project, pk=project_id)
-            if request.user.is_authenticated() and project.memberships.filter(user=request.user).exists():
-                return queryset.filter(memberships__project=project).distinct()
-            else:
-                raise exc.PermissionDenied(_("You don't have permisions to see this project users."))
-
-        if request.user.is_superuser:
-            return queryset
-
-        return []
-
+######################################################
+## User
+######################################################
 
 class UsersViewSet(ModelCrudViewSet):
     permission_classes = (permissions.UserPermission,)
@@ -73,7 +61,9 @@ class UsersViewSet(ModelCrudViewSet):
         raise exc.NotSupported()
 
     def list(self, request, *args, **kwargs):
-        self.object_list = MembersFilterBackend().filter_queryset(request, self.get_queryset(), self)
+        self.object_list = MembersFilterBackend().filter_queryset(request,
+                                                                  self.get_queryset(),
+                                                                  self)
 
         page = self.paginate_queryset(self.object_list)
         if page is not None:
@@ -249,12 +239,14 @@ class UsersViewSet(ModelCrudViewSet):
         """
         serializer = serializers.ChangeEmailSerializer(data=request.DATA, many=False)
         if not serializer.is_valid():
-            raise exc.WrongArguments(_("Invalid, are you sure the token is correct and you didn't use it before?"))
+            raise exc.WrongArguments(_("Invalid, are you sure the token is correct and you "
+                                       "didn't use it before?"))
 
         try:
             user = models.User.objects.get(email_token=serializer.data["email_token"])
         except models.User.DoesNotExist:
-            raise exc.WrongArguments(_("Invalid, are you sure the token is correct and you didn't use it before?"))
+            raise exc.WrongArguments(_("Invalid, are you sure the token is correct and you "
+                                       "didn't use it before?"))
 
         self.check_permissions(request, "change_email", user)
         user.email = user.new_email
@@ -304,3 +296,25 @@ class UsersViewSet(ModelCrudViewSet):
         user_cancel_account_signal.send(sender=user.__class__, user=user, request_data=request_data)
         user.cancel()
         return Response(status=status.HTTP_204_NO_CONTENT)
+
+
+######################################################
+## Role
+######################################################
+
+class RolesViewSet(ModelCrudViewSet):
+    model = models.Role
+    serializer_class = serializers.RoleSerializer
+    permission_classes = (permissions.RolesPermission, )
+    filter_backends = (filters.CanViewProjectFilterBackend,)
+    filter_fields = ('project',)
+
+    def pre_delete(self, obj):
+        move_to = self.request.QUERY_PARAMS.get('moveTo', None)
+        if move_to:
+            membership_model = apps.get_model("projects", "Membership")
+            role_dest = get_object_or_404(self.model, project=obj.project, id=move_to)
+            qs = membership_model.objects.filter(project_id=obj.project.pk, role=obj)
+            qs.update(role=role_dest)
+
+        super().pre_delete(obj)
diff --git a/taiga/users/models.py b/taiga/users/models.py
index 83226725..e2ffe491 100644
--- a/taiga/users/models.py
+++ b/taiga/users/models.py
@@ -174,6 +174,7 @@ class User(AbstractBaseUser, PermissionsMixin):
         self.save()
         self.auth_data.all().delete()
 
+
 class Role(models.Model):
     name = models.CharField(max_length=200, null=False, blank=False,
                             verbose_name=_("name"))
diff --git a/taiga/users/permissions.py b/taiga/users/permissions.py
index 5b7a8f27..cbabe22c 100644
--- a/taiga/users/permissions.py
+++ b/taiga/users/permissions.py
@@ -14,9 +14,13 @@
 # You should have received a copy of the GNU Affero General Public License
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
-from taiga.base.api.permissions import (TaigaResourcePermission, IsSuperUser,
-                                        AllowAny, PermissionComponent,
-                                        IsAuthenticated)
+from taiga.base.api.permissions import TaigaResourcePermission
+from taiga.base.api.permissions import IsSuperUser
+from taiga.base.api.permissions import AllowAny
+from taiga.base.api.permissions import IsAuthenticated
+from taiga.base.api.permissions import HasProjectPerm
+from taiga.base.api.permissions import IsProjectOwner
+from taiga.base.api.permissions import PermissionComponent
 
 
 class IsTheSameUser(PermissionComponent):
@@ -39,3 +43,11 @@ class UserPermission(TaigaResourcePermission):
     remove_avatar_perms = IsAuthenticated()
     starred_perms = AllowAny()
     change_email_perms = IsTheSameUser()
+
+
+class RolesPermission(TaigaResourcePermission):
+    retrieve_perms = HasProjectPerm('view_project')
+    create_perms = IsProjectOwner()
+    update_perms = IsProjectOwner()
+    destroy_perms = IsProjectOwner()
+    list_perms = AllowAny()
diff --git a/taiga/users/serializers.py b/taiga/users/serializers.py
index 5fb28310..acd42741 100644
--- a/taiga/users/serializers.py
+++ b/taiga/users/serializers.py
@@ -16,16 +16,24 @@
 
 from django.core import validators
 from django.core.exceptions import ValidationError
+from django.utils.translation import ugettext_lazy as _
 
 from rest_framework import serializers
+from taiga.base.serializers import Serializer
+from taiga.base.serializers import ModelSerializer
+from taiga.base.serializers import PgArrayField
 
-from .models import User
+from .models import User, Role
 from .services import get_photo_or_gravatar_url, get_big_photo_or_gravatar_url
 
 import re
 
 
-class UserSerializer(serializers.ModelSerializer):
+######################################################
+## User
+######################################################
+
+class UserSerializer(ModelSerializer):
     full_name_display = serializers.SerializerMethodField("get_full_name_display")
     photo = serializers.SerializerMethodField("get_photo")
     big_photo = serializers.SerializerMethodField("get_big_photo")
@@ -39,16 +47,19 @@ class UserSerializer(serializers.ModelSerializer):
 
     def validate_username(self, attrs, source):
         value = attrs[source]
-        validator = validators.RegexValidator(re.compile('^[\w.-]+$'), "invalid username", "invalid")
+        validator = validators.RegexValidator(re.compile('^[\w.-]+$'), _("invalid username"),
+                                              _("invalid"))
 
         try:
             validator(value)
         except ValidationError:
-            raise serializers.ValidationError("Required. 255 characters or fewer. Letters, numbers "
-                                              "and /./-/_ characters'")
+            raise serializers.ValidationError(_("Required. 255 characters or fewer. Letters, "
+                                                "numbers and /./-/_ characters'"))
 
-        if self.object and self.object.username != value and User.objects.filter(username=value).exists():
-            raise serializers.ValidationError("Invalid username. Try with a different one.")
+        if (self.object and
+                self.object.username != value and
+                User.objects.filter(username=value).exists()):
+            raise serializers.ValidationError(_("Invalid username. Try with a different one."))
 
         return attrs
 
@@ -62,14 +73,36 @@ class UserSerializer(serializers.ModelSerializer):
         return get_big_photo_or_gravatar_url(user)
 
 
-class RecoverySerializer(serializers.Serializer):
+class RecoverySerializer(Serializer):
     token = serializers.CharField(max_length=200)
     password = serializers.CharField(min_length=6)
 
 
-class ChangeEmailSerializer(serializers.Serializer):
+class ChangeEmailSerializer(Serializer):
     email_token = serializers.CharField(max_length=200)
 
 
-class CancelAccountSerializer(serializers.Serializer):
+class CancelAccountSerializer(Serializer):
     cancel_token = serializers.CharField(max_length=200)
+
+
+######################################################
+## Role
+######################################################
+
+class RoleSerializer(ModelSerializer):
+    members_count = serializers.SerializerMethodField("get_members_count")
+    permissions = PgArrayField(required=False)
+
+    class Meta:
+        model = Role
+        fields = ('id', 'name', 'permissions', 'computable', 'project', 'order', 'members_count')
+
+    def get_members_count(self, obj):
+        return obj.memberships.count()
+
+
+class ProjectRoleSerializer(ModelSerializer):
+    class Meta:
+        model = Role
+        fields = ('id', 'name', 'slug', 'order', 'computable')
diff --git a/tests/integration/resources_permissions/test_projects_choices_resources.py b/tests/integration/resources_permissions/test_projects_choices_resources.py
index ed0a6a77..0c31df3d 100644
--- a/tests/integration/resources_permissions/test_projects_choices_resources.py
+++ b/tests/integration/resources_permissions/test_projects_choices_resources.py
@@ -2,6 +2,7 @@ from django.core.urlresolvers import reverse
 
 from taiga.base.utils import json
 from taiga.projects import serializers
+from taiga.users.serializers import RoleSerializer
 from taiga.permissions.permissions import MEMBERS_PERMISSIONS
 
 from tests import factories as f
@@ -140,19 +141,19 @@ def test_roles_update(client, data):
         data.project_owner
     ]
 
-    role_data = serializers.RoleSerializer(data.public_project.roles.all()[0]).data
+    role_data = RoleSerializer(data.public_project.roles.all()[0]).data
     role_data["name"] = "test"
     role_data = json.dumps(role_data)
     results = helper_test_http_method(client, 'put', public_url, role_data, users)
     assert results == [401, 403, 403, 403, 200]
 
-    role_data = serializers.RoleSerializer(data.private_project1.roles.all()[0]).data
+    role_data = RoleSerializer(data.private_project1.roles.all()[0]).data
     role_data["name"] = "test"
     role_data = json.dumps(role_data)
     results = helper_test_http_method(client, 'put', private1_url, role_data, users)
     assert results == [401, 403, 403, 403, 200]
 
-    role_data = serializers.RoleSerializer(data.private_project2.roles.all()[0]).data
+    role_data = RoleSerializer(data.private_project2.roles.all()[0]).data
     role_data["name"] = "test"
     role_data = json.dumps(role_data)
     results = helper_test_http_method(client, 'put', private2_url, role_data, users)