diff --git a/Gemfile b/Gemfile
index 45f16f7b4..d393a76b3 100644
--- a/Gemfile
+++ b/Gemfile
@@ -25,7 +25,7 @@ gem 'sdoc', '~> 0.4.0', group: :doc
 gem 'devise'
 # Use ActiveModel has_secure_password
 # gem 'bcrypt', '~> 3.1.7'
-
+gem 'acts_as_commentable_with_threading'
 # Use Unicorn as the app server
 # gem 'unicorn'
 
diff --git a/Gemfile.lock b/Gemfile.lock
index 01408b9c2..f9cb656a5 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -36,7 +36,13 @@ GEM
       minitest (~> 5.1)
       thread_safe (~> 0.3, >= 0.3.4)
       tzinfo (~> 1.1)
+    acts_as_commentable_with_threading (2.0.0)
+      activerecord (>= 4.0)
+      activesupport (>= 4.0)
+      awesome_nested_set (>= 3.0)
     arel (6.0.2)
+    awesome_nested_set (3.0.2)
+      activerecord (>= 4.0.0, < 5)
     bcrypt (3.1.10)
     binding_of_caller (0.7.2)
       debug_inspector (>= 0.0.1)
@@ -188,6 +194,7 @@ PLATFORMS
   ruby
 
 DEPENDENCIES
+  acts_as_commentable_with_threading
   byebug
   capybara
   coffee-rails (~> 4.1.0)
diff --git a/app/models/comment.rb b/app/models/comment.rb
new file mode 100644
index 000000000..3f8dd83f4
--- /dev/null
+++ b/app/models/comment.rb
@@ -0,0 +1,19 @@
+class Comment < ActiveRecord::Base
+  acts_as_nested_set :scope => [:commentable_id, :commentable_type]
+
+  validates :body, :presence => true
+  validates :user, :presence => true
+
+  belongs_to :commentable, :polymorphic => true
+  belongs_to :user
+
+  def self.build(commentable, user, body)
+    new commentable: commentable,
+        user_id:     user.id,
+        body:        body
+  end
+
+  def self.find_parent(params)
+    params[:commentable_type].constantize.find(params[:commentable_id])
+  end
+end
diff --git a/app/models/debate.rb b/app/models/debate.rb
index c66913c59..5a11c02cb 100644
--- a/app/models/debate.rb
+++ b/app/models/debate.rb
@@ -1,4 +1,6 @@
 class Debate < ActiveRecord::Base
+  acts_as_commentable
+  
   validates :title, presence: true
   validates :description, presence: true
 
diff --git a/db/migrate/20150718091702_acts_as_commentable_with_threading_migration.rb b/db/migrate/20150718091702_acts_as_commentable_with_threading_migration.rb
new file mode 100644
index 000000000..728b26b9e
--- /dev/null
+++ b/db/migrate/20150718091702_acts_as_commentable_with_threading_migration.rb
@@ -0,0 +1,21 @@
+class ActsAsCommentableWithThreadingMigration < ActiveRecord::Migration
+  def self.up
+    create_table :comments, :force => true do |t|
+      t.integer :commentable_id
+      t.string :commentable_type
+      t.string :title
+      t.text :body
+      t.string :subject
+      t.integer :user_id, :null => false
+      t.integer :parent_id, :lft, :rgt
+      t.timestamps
+    end
+
+    add_index :comments, :user_id
+    add_index :comments, [:commentable_id, :commentable_type]
+  end
+
+  def self.down
+    drop_table :comments
+  end
+end
diff --git a/db/schema.rb b/db/schema.rb
index 61fb86a58..56966e1dc 100644
--- a/db/schema.rb
+++ b/db/schema.rb
@@ -11,7 +11,24 @@
 #
 # It's strongly recommended that you check this file into your version control system.
 
-ActiveRecord::Schema.define(version: 20150716174358) do
+ActiveRecord::Schema.define(version: 20150718091702) do
+
+  create_table "comments", force: :cascade do |t|
+    t.integer  "commentable_id"
+    t.string   "commentable_type"
+    t.string   "title"
+    t.text     "body"
+    t.string   "subject"
+    t.integer  "user_id",          null: false
+    t.integer  "parent_id"
+    t.integer  "lft"
+    t.integer  "rgt"
+    t.datetime "created_at"
+    t.datetime "updated_at"
+  end
+
+  add_index "comments", ["commentable_id", "commentable_type"], name: "index_comments_on_commentable_id_and_commentable_type"
+  add_index "comments", ["user_id"], name: "index_comments_on_user_id"
 
   create_table "debates", force: :cascade do |t|
     t.string   "title"