diff --git a/app/helpers/email_template_helper.rb b/app/helpers/email_template_helper.rb
new file mode 100644
index 0000000..5769e1f
--- /dev/null
+++ b/app/helpers/email_template_helper.rb
@@ -0,0 +1,9 @@
+module EmailTemplateHelper
+
+  def mail_with_template(params={})
+    params[:body] = params[:email_template].present? ? params[:email_template].parsed_body(params[:template_params]) : params[:body]
+    params[:subject] = params[:email_template].present? ? params[:email_template].parsed_subject(params[:template_params]) : params[:subject]
+    mail(params.except(:email_template))
+  end
+
+end
diff --git a/app/mailers/user_mailer.rb b/app/mailers/user_mailer.rb
index 93efd25..259e83b 100644
--- a/app/mailers/user_mailer.rb
+++ b/app/mailers/user_mailer.rb
@@ -1,4 +1,7 @@
 class UserMailer < ActionMailer::Base
+
+  include EmailTemplateHelper
+
   def activation_email_notify(user)
     user_email = "#{user.login}@#{user.email_domain}"
     @name = user.name
@@ -22,10 +25,12 @@ class UserMailer < ActionMailer::Base
     @redirection = (true if user.return_to)
     @join = (user.community_to_join if user.community_to_join)
 
-    mail(
+    mail_with_template(
       from: "#{user.environment.name} <#{user.environment.contact_email}>",
       to: user.email,
       subject: _("[%s] Activate your account") % [user.environment.name],
+      template_params: {:environment => user.environment, :activation_code => @activation_code, :redirection => @redirection, :join => @join},
+      email_template: user.environment.email_templates.find_by_template_type(:user_activation),
     )
   end
 
diff --git a/app/models/email_template.rb b/app/models/email_template.rb
index 557bd56..3be426a 100644
--- a/app/models/email_template.rb
+++ b/app/models/email_template.rb
@@ -6,6 +6,10 @@ class EmailTemplate < ActiveRecord::Base
 
   validates_presence_of :name
 
+  validates :name, uniqueness: { scope: [:owner_type, :owner_id] }
+
+  validates :template_type, uniqueness: { scope: [:owner_type, :owner_id] }, if: :unique_by_type?
+
   def parsed_body(params)
     @parsed_body ||= parse(body, params)
   end
@@ -18,10 +22,15 @@ class EmailTemplate < ActiveRecord::Base
     HashWithIndifferentAccess.new ({
       :task_rejection => {:description => _('Task Rejection')},
       :task_acceptance => {:description => _('Task Acceptance')},
-      :organization_members => {:description => _('Organization Members')}
+      :organization_members => {:description => _('Organization Members')},
+      :user_activation => {:description => _('User Activation'), :unique => true}
     })
   end
 
+  def unique_by_type?
+    available_types.fetch(template_type, {})[:unique]
+  end
+
   protected
 
   def parse(source, params)
diff --git a/app/models/environment.rb b/app/models/environment.rb
index a80323f..2ee1c98 100644
--- a/app/models/environment.rb
+++ b/app/models/environment.rb
@@ -21,6 +21,7 @@ class Environment < ActiveRecord::Base
 
   has_many :tasks, :dependent => :destroy, :as => 'target'
   has_many :search_terms, :as => :context
+  has_many :email_templates, :foreign_key => :owner_id
 
   IDENTIFY_SCRIPTS = /(php[0-9s]?|[sp]htm[l]?|pl|py|cgi|rb)/
 
diff --git a/test/unit/email_template_helper_test.rb b/test/unit/email_template_helper_test.rb
new file mode 100644
index 0000000..eaaeb97
--- /dev/null
+++ b/test/unit/email_template_helper_test.rb
@@ -0,0 +1,20 @@
+require_relative "../test_helper"
+
+class EmailTemplateHelperTest < ActionView::TestCase
+
+  should 'replace body and subject with parsed values from template' do
+    template = mock
+    template.expects(:parsed_body).returns('parsed body')
+    template.expects(:parsed_subject).returns('parsed subject')
+    params = {:subject => 'subject', :body => 'body', :email_template => template}
+    expects(:mail).with({:subject => 'parsed subject', :body => 'parsed body'})
+    mail_with_template(params)
+  end
+
+  should 'do not change params if there is no email template' do
+    params = {:subject => 'subject', :body => 'body'}
+    expects(:mail).with(params)
+    mail_with_template(params)
+  end
+
+end
diff --git a/test/unit/email_template_test.rb b/test/unit/email_template_test.rb
index d0f8e97..e29894f 100644
--- a/test/unit/email_template_test.rb
+++ b/test/unit/email_template_test.rb
@@ -19,4 +19,25 @@ class EmailTemplateTest < ActiveSupport::TestCase
     assert_equal 'Hi John', template.parsed_subject({:person => 'John'})
   end
 
+  should 'not create template with the same name of other' do
+    template1 = EmailTemplate.new(:template_type => :type1, :name => 'template')
+    template2 = EmailTemplate.new(:template_type => :type1, :name => 'template')
+    assert template1.save
+    assert !template2.save
+  end
+
+  should 'not create duplicated template when template type is unique' do
+    template1 = EmailTemplate.new(:template_type => :user_activation, :name => 'template1')
+    template2 = EmailTemplate.new(:template_type => :user_activation, :name => 'template2')
+    assert template1.save
+    assert !template2.save
+  end
+
+  should 'create duplicated template when template type is not unique' do
+    template1 = EmailTemplate.new(:template_type => :task_rejection, :name => 'template1')
+    template2 = EmailTemplate.new(:template_type => :task_rejection, :name => 'template2')
+    assert template1.save
+    assert template2.save
+  end
+
 end
diff --git a/test/unit/user_mailer_test.rb b/test/unit/user_mailer_test.rb
index b119336..92770aa 100644
--- a/test/unit/user_mailer_test.rb
+++ b/test/unit/user_mailer_test.rb
@@ -26,6 +26,24 @@ fast_create(Person))
     assert_match /profile\/some-user\/friends\/suggest/, email.body.to_s
   end
 
+  should 'deliver activation code email' do
+    assert_difference 'ActionMailer::Base.deliveries.size' do
+      u = create_user('some-user')
+      UserMailer.activation_code(u).deliver
+    end
+  end
+
+  should 'deliver activation code email with template' do
+    EmailTemplate.create!(:template_type => :user_activation, :name => 'template1', :subject => 'activation template subject', :body => 'activation template body', :owner => Environment.default)
+    assert_difference 'ActionMailer::Base.deliveries.size' do
+      u = create_user('some-user')
+      UserMailer.activation_code(u).deliver
+    end
+    mail = ActionMailer::Base.deliveries.last
+    assert_equal 'activation template subject', mail.subject.to_s
+    assert_equal 'activation template body', mail.body.to_s
+  end
+
   private
 
     def read_fixture(action)
--
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