diff --git a/test/factories/groups.rb b/test/factories/groups.rb
index 74b3b5b9..d63079b8 100644
--- a/test/factories/groups.rb
+++ b/test/factories/groups.rb
@@ -1,6 +1,17 @@
 FactoryGirl.define do
-  factory :group do
+  factory :group do 
     name { Faker::Lorem.word }
     description { Faker::Lorem.sentence }
+    members {|a| [a.association(:user)]}
+
+    factory :group_with_invitations do
+      transient do
+        invitations_count 1
+      end
+      after(:create) do |group, evaluator|
+        create_list(:group_invitation, evaluator.invitations_count, group: group)
+      end
+    end
+    
   end
 end
diff --git a/test/models/group_test.rb b/test/models/group_test.rb
index 1e160e47..f21c351c 100644
--- a/test/models/group_test.rb
+++ b/test/models/group_test.rb
@@ -1,11 +1,92 @@
 require "test_helper"
 
 class GroupTest < ActiveSupport::TestCase
-  def group
-    @group ||= Group.new
+
+  def test_name_must_be_present
+    group = build(:group,:name => nil)
+    group.valid?
+    assert_not_empty group.errors[:name]
+  end
+
+  def test_description_must_be_present
+    group = build(:group,:description => nil)
+    group.valid?
+    assert_not_empty group.errors[:description]
+  end
+
+  def test_group_owner_should_be_present
+    group = create(:group)
+    user = create(:user)
+    group.owner = user
+    assert_not_nil group.owner
+  end
+
+  def test_user_is_a_member_of_a_group
+    group = create(:group)
+    user = create(:user)
+    group.members << user
+    assert group.member?(user)
+  end
+
+  def test_user_is_not_a_member_of_a_group
+    group = create(:group)
+    user = create(:user)
+    assert_not group.member?(user)
+  end
+
+  def test_group_should_not_accept_invitation_if_token_is_not_present
+    group = create(:group)
+    token = SecureRandom.base64(24).tr('0+/=', 'A0lk')
+    assert_not group.accept_invitation(token)
+  end
+
+  def test_group_must_accept_invitation_having_token_with_them
+    group = create(:group)
+    invitation = create(:group_invitation)
+    group.group_invitations << invitation
+    user = create(:user)
+    user.group_invitations << invitation
+    assert group.accept_invitation(invitation.token)
+  end
+
+  def test_user_is_not_invited_if_group_invitation_is_not_present
+    group = create(:group)
+    user = create(:user)
+    assert_not group.invited?
+  end
+
+  def test_user_is_invited_if_group_invitation_is_present
+    group = create(:group)
+    user = create(:user)
+    invitation = create(:group_invitation, user: user)
+    group.group_invitations << invitation
+    assert group.invited?(user: user)
+  end
+
+  def test_group_member_not_removed_if_member_is_the_owner
+    group = create(:group)
+    member = create(:user)
+    group.members << member
+    group.owner = member
+    assert_not group.can_remove_member?(member)
+  end
+
+  def test_group_member_removed_if_current_user_is_member
+    member = create(:user)
+    group = create(:group)
+    group.members << member
+    current_user = member
+    group.owner = group.members.first
+    assert group.can_remove_member?(member, current_user)
   end
 
-  def test_valid
-    assert group.valid?
+  def test_group_member_current_user_removed_if_current_user_is_owner
+    member = create(:user)
+    group = create(:group)
+    group.members << member
+    current_user = group.members.first
+    group.owner = current_user
+    assert group.can_remove_member?(member, current_user)
   end
+  
 end