diff --git a/app/assets/stylesheets/osem.css.scss b/app/assets/stylesheets/osem.css.scss
index 83a921a6..03c221da 100644
--- a/app/assets/stylesheets/osem.css.scss
+++ b/app/assets/stylesheets/osem.css.scss
@@ -1,13 +1,13 @@
 html {
-    position: relative;
-    min-height: 100%;
+  position: relative;
+  min-height: 100%;
 }
 
 body {
-    /* Margin bottom by 2 times the footer height */
-    margin-bottom: 60px;
-    /* Margin bottom by navbar height */
-    padding-top: 60px;
+  /* Margin bottom by 2 times the footer height */
+  margin-bottom: 60px;
+  /* Margin bottom by navbar height */
+  padding-top: 60px;
 }
 
 #content {
@@ -15,23 +15,23 @@ body {
 }
 
 #footer {
-    position: absolute;
-    bottom: 0;
-    width: 100%;
-    /* Set the fixed height of the footer here */
-    height: 60px;
-    background-color: #f5f5f5;
-    .container {
-      padding: 15px;
-    }
+  position: absolute;
+  bottom: 0;
+  width: 100%;
+  /* Set the fixed height of the footer here */
+  height: 60px;
+  background-color: #f5f5f5;
+  .container {
+    padding: 15px;
+  }
 }
 
 .nav-tabs {
-    margin-bottom: 15px;
+  margin-bottom: 15px;
 }
 
 .img-center {
-    margin: 0 auto;
+  margin: 0 auto;
 }
 
 /* centered columns styles */
@@ -71,4 +71,14 @@ p.comment-body {
 
 #account-already {
   font-size: 0.6em;
-}
\ No newline at end of file
+}
+
+/* comments views pane: use padding-bottom before next comment box */
+.panel.panel-default .panel-body .notifications {
+  padding-bottom: 20px;
+}
+
+/* comments views pane: use padding-bottom after each comment */
+.panel.panel-default .panel-body .notifications p {
+  padding-bottom: 20px;
+}
diff --git a/app/controllers/admin/comments_controller.rb b/app/controllers/admin/comments_controller.rb
new file mode 100644
index 00000000..874439df
--- /dev/null
+++ b/app/controllers/admin/comments_controller.rb
@@ -0,0 +1,28 @@
+module Admin
+  class CommentsController < Admin::BaseController
+    load_and_authorize_resource
+
+    def index
+      # All available comments, grouped and sorted
+      @comments = grouped_comments(accessible_ordered_comments)
+
+      # Grouped, sorted, available comments, posted since current_user last login
+      @unread_comments = grouped_comments(accessible_ordered_comments.find_since_last_login(current_user))
+
+      # Grouped, sorted, available comments, posted by current_user
+      @posted_comments = grouped_comments(accessible_ordered_comments.find_comments_by_user(current_user))
+    end
+
+    private
+
+    # Returning all available comments, ordered by created_at: :desc and by event.title
+    def accessible_ordered_comments
+      Comment.accessible_by(current_ability).joins('INNER JOIN events ON commentable_id = events.id').order('events.title', 'comments.created_at DESC')
+    end
+
+# Grouping all comments by conference, and by event. It returns {:conference => {:event => [{comment_2}, {comment_1 }]}}
+    def grouped_comments(remarks)
+      remarks.group_by{ |comment| comment.commentable.conference }.map {|conference, comments| [conference, comments.group_by{|comment| comment.commentable}]}.to_h
+    end
+  end
+end
diff --git a/app/helpers/application_helper.rb b/app/helpers/application_helper.rb
index 7e9f7652..4c72b3dc 100644
--- a/app/helpers/application_helper.rb
+++ b/app/helpers/application_helper.rb
@@ -278,4 +278,8 @@ module ApplicationHelper
       new_user_registration_path
     end
   end
+
+  def unread_notifications(user)
+    Comment.accessible_by(current_ability).find_since_last_login(user)
+  end
 end
diff --git a/app/mailers/mailbot.rb b/app/mailers/mailbot.rb
index 9cf89b88..e8118382 100644
--- a/app/mailers/mailbot.rb
+++ b/app/mailers/mailbot.rb
@@ -80,6 +80,22 @@ class Mailbot < ActionMailer::Base
     end
   end
 
+  def send_notification_email_for_comment(comment)
+    @comment = comment
+    @event = @comment.commentable
+    @conference = @event.conference
+    recipients = User.comment_notifiable(@conference) # with scope
+    recipients.each do |user|
+      @user = user
+      mail(to: @user.email,
+           from: @conference.contact.email,
+           reply_to: @conference.contact.email,
+           template_path: 'admin/emails',
+           template_name: 'comment_template',
+           subject: "New comment has been posted for #{@event.title}")
+    end
+  end
+
   def build_email(conference, to, subject, body)
     mail(to: to,
          from: conference.contact.email,
diff --git a/app/models/ability.rb b/app/models/ability.rb
index 0f89057e..bd30a8fd 100644
--- a/app/models/ability.rb
+++ b/app/models/ability.rb
@@ -88,12 +88,13 @@ class Ability
     # Abilities from not_signed_in and signed_in are also inherited
     signed_in(user)
 
-    signed_in_with_organizer_role(user)
-    signed_in_with_cfp_role(user)
-    signed_in_with_info_desk_role(user)
-    signed_in_with_volunteers_coordinator_role(user)
+    signed_in_with_organizer_role(user) if user.has_role? :organizer, :any
+    signed_in_with_cfp_role(user) if user.has_role? :cfp, :any
+    signed_in_with_info_desk_role(user) if user.has_role? :info_desk, :any
+    signed_in_with_volunteers_coordinator_role(user) if user.has_role? :volunteer_coordinator, :any
 
     # for users with any role
+    can :access, Admin
     can [:show], Conference
     can :index, Commercial, commercialable_type: 'Conference'
     cannot [:edit, :update, :destroy], Question, global: true
@@ -137,6 +138,8 @@ class Ability
     can :manage, Sponsor, conference_id: conf_ids_for_organizer
     can :manage, SponsorshipLevel, conference_id: conf_ids_for_organizer
     can :manage, Ticket, conference_id: conf_ids_for_organizer
+    can :index, Comment, commentable_type: 'Event',
+                         commentable_id: Event.where(conference_id: conf_ids_for_organizer).pluck(:id)
   end
 
   def signed_in_with_cfp_role(user)
@@ -155,6 +158,8 @@ class Ability
     can :manage, CallForPaper, conference_id: conf_ids_for_cfp
     can :manage, Commercial, commercialable_type: 'Event',
                              commercialable_id: Event.where(conference_id: conf_ids_for_cfp).pluck(:id)
+    can :index, Comment, commentable_type: 'Event',
+                         commentable_id: Event.where(conference_id: conf_ids_for_cfp).pluck(:id)
   end
 
   def signed_in_with_info_desk_role(user)
diff --git a/app/models/comment.rb b/app/models/comment.rb
index 6196856e..f668afb3 100644
--- a/app/models/comment.rb
+++ b/app/models/comment.rb
@@ -3,6 +3,7 @@ class Comment < ActiveRecord::Base
   attr_accessible :commentable, :body, :user_id
   validates_presence_of :body
   validates_presence_of :user
+  after_create :send_notification
 
   # NOTE: install the acts_as_votable plugin if you
   # want user to vote on the quality of comments.
@@ -40,9 +41,18 @@ class Comment < ActiveRecord::Base
     where(commentable_type: commentable_str.to_s, commentable_id: commentable_id).order('created_at DESC')
   }
 
+  scope :find_since_last_login, lambda { |user|
+    where(created_at: (user.last_sign_in_at..Time.now)).order(created_at: :desc)
+  }
   # Helper class method to look up a commentable object
   # given the commentable class name and id
   def self.find_commentable(commentable_str, commentable_id)
     commentable_str.constantize.find(commentable_id)
   end
+
+  private
+
+  def send_notification
+    Mailbot.delay.send_notification_email_for_comment(self)
+  end
 end
diff --git a/app/models/email_settings.rb b/app/models/email_settings.rb
index 11a7b628..5642b4da 100644
--- a/app/models/email_settings.rb
+++ b/app/models/email_settings.rb
@@ -49,7 +49,7 @@ class EmailSettings < ActiveRecord::Base
       h['registration_end_date'] = conference.registration_period.end_date
     end
 
-    if !event.nil?
+    if event
       h['eventtitle'] = event.title
       h['proposalslink'] = Rails.application.routes.url_helpers.conference_proposal_index_url(
                            conference.short_title, host: CONFIG['url_for_emails'])
@@ -67,6 +67,8 @@ class EmailSettings < ActiveRecord::Base
     parse_template(conf_update_template, values)
   end
 
+  private
+
   def parse_template(text, values)
     values.each do |key, value|
       if value.kind_of?(Date)
diff --git a/app/models/user.rb b/app/models/user.rb
index 6214d07a..568a1c89 100644
--- a/app/models/user.rb
+++ b/app/models/user.rb
@@ -11,6 +11,9 @@ class User < ActiveRecord::Base
 
   before_create :setup_role
 
+  # add scope
+  scope :comment_notifiable, ->(conference) {joins(:roles).where('roles.name IN (?)', [:organizer, :cfp]).where('roles.resource_type = ? AND roles.resource_id = ?', 'Conference', conference.id)}
+
   # Include default devise modules. Others available are:
   # :token_authenticatable, :confirmable,
   # :lockable, :timeoutable and :omniauthable
diff --git a/app/views/admin/comments/_all_comments.html.haml b/app/views/admin/comments/_all_comments.html.haml
new file mode 100644
index 00000000..02ad15e8
--- /dev/null
+++ b/app/views/admin/comments/_all_comments.html.haml
@@ -0,0 +1,12 @@
+- @comments.each do |conference, events|
+  .panel.panel-default
+    .panel-heading
+      %h4.title.panel-title= conference.title
+    .panel-body
+      - events.each do |event, comments|
+        .notifications
+          %h4.title= link_to event.title, admin_conference_event_path(event.conference.short_title, event)
+          %hr
+          - comments.each do |comment|
+            %h5.strong Posted by: #{comment.user.name} | Created at: #{comment.created_at}
+            %p= comment.body
diff --git a/app/views/admin/comments/_posted_comments.html.haml b/app/views/admin/comments/_posted_comments.html.haml
new file mode 100644
index 00000000..89c90519
--- /dev/null
+++ b/app/views/admin/comments/_posted_comments.html.haml
@@ -0,0 +1,12 @@
+- @posted_comments.each do |conference, events|
+  .panel.panel-default
+    .panel-heading
+      %h4.title.panel-title= conference.title
+    .panel-body
+      - events.each do |event, comments|
+        .notifications
+          %h4.title= link_to event.title, admin_conference_event_path(event.conference.short_title, event)
+          %hr
+          - comments.each do |comment|
+            %h5.strong Created at: #{comment.created_at}
+            %p= comment.body
diff --git a/app/views/admin/comments/_unread_comments.html.haml b/app/views/admin/comments/_unread_comments.html.haml
new file mode 100644
index 00000000..9291aa83
--- /dev/null
+++ b/app/views/admin/comments/_unread_comments.html.haml
@@ -0,0 +1,12 @@
+- @unread_comments.each do |conference, events|
+  .panel.panel-default
+    .panel-heading
+      %h4.title.panel-title= conference.title
+    .panel-body
+      - events.each do |event, comments|
+        .notifications
+          %h4.title= link_to event.title, admin_conference_event_path(event.conference.short_title, event)
+          %hr
+          - comments.each do |comment|
+            %h5.strong Posted by: #{comment.user.name} | Created at: #{comment.created_at}
+            %p= comment.body
diff --git a/app/views/admin/comments/index.html.haml b/app/views/admin/comments/index.html.haml
new file mode 100644
index 00000000..9a141c85
--- /dev/null
+++ b/app/views/admin/comments/index.html.haml
@@ -0,0 +1,24 @@
+%h1 Comments
+%br
+.row
+  .col-md-12
+    %ul.nav.nav-tabs#commentsTable
+      %li.active
+        %a{:href=>"#unread_comments", "data-toggle"=>"tab"}
+          %span.fa.fa-comment
+          Unread
+      %li
+        %a{:href=>"#posted_comments", "data-toggle"=>"tab"}
+          %span.fa.fa-pencil
+          Posted
+      %li
+        %a{:href=>"#all_comments", "data-toggle"=>"tab"}
+          %span.fa.fa-comments-o
+          All
+    .tab-content
+      .tab-pane.active#unread_comments
+        = render partial: 'unread_comments'
+      .tab-pane#posted_comments
+        = render partial: 'posted_comments'
+      .tab-pane#all_comments
+        = render partial: 'all_comments'
diff --git a/app/views/admin/emails/comment_template.text.erb b/app/views/admin/emails/comment_template.text.erb
new file mode 100644
index 00000000..0ebd8ad4
--- /dev/null
+++ b/app/views/admin/emails/comment_template.text.erb
@@ -0,0 +1,10 @@
+Dear <%= @user.name %>,
+
+User <%= @comment.user.name %> posted a new comment for event <%= @event.title %> of <%= @conference.short_title %> .
+
+"<%= @comment.body %>"
+
+To reply to this comment, please go to <%=  h( admin_conference_event_url(@conference.short_title, @event)) %>
+
+Best wishes,
+<%= @conference.short_title %> Team
diff --git a/app/views/layouts/_navigation.html.haml b/app/views/layouts/_navigation.html.haml
index ea837d2c..cf2b3b44 100644
--- a/app/views/layouts/_navigation.html.haml
+++ b/app/views/layouts/_navigation.html.haml
@@ -13,17 +13,34 @@
         %ul.nav.navbar-nav#splash-nav
           = content_for :splash_nav
       -if user_signed_in?
-        %ul.nav.navbar-nav.navbar-right
-          %li.dropdown
-            %a.dropdown-toggle{"data-toggle" => "dropdown", :href => "#", id: "current-user-detail"}
-              - if not current_user.name.blank?
-                #{current_user.name}
-              -else
-                #{current_user.email}
-              = image_tag(current_user.gravatar_url(size: '18'), title: "Yo #{current_user.name}!", :alt => '')
-              %b.caret
-            %ul.dropdown-menu
-              = render 'layouts/user_menu'
+        .btn-group.pull-right
+          %ul.nav.navbar-nav.navbar-right
+            %li.dropdown
+              %a.dropdown-toggle{"data-toggle" => "dropdown", :href => "#", id: "current-user-detail"}
+                - if not current_user.name.blank?
+                  #{current_user.name}
+                -else
+                  #{current_user.email}
+                = image_tag(current_user.gravatar_url(size: '18'), title: "Yo #{current_user.name}!", :alt => '')
+                %b.caret
+              %ul.dropdown-menu
+                = render 'layouts/user_menu'
+          - if can? :index, Comment
+            %ul.nav.navbar-nav.navbar-right
+              %li.dropdown
+                %a.dropdown-toggle{"data-toggle" => "dropdown", :href => "#"}
+                  - if unread_notifications(current_user)
+                    Notifications (#{unread_notifications(current_user).length})
+                    %span.fa.fa-comment
+                    %b.caret
+                    %ul.dropdown-menu
+                      - if unread_notifications(current_user).length > 0
+                        %li.dropdown-header Last 5 Comments for:
+                        - unread_notifications(current_user).limit(5).group_by{ |comment| comment.commentable}.each do |event, comments|
+                          %li= link_to("#{event.title}(#{comments.count})", admin_conference_event_path(event.conference.short_title, event.id))
+                        %li.divider
+                        %li= link_to "See all unread Comments (#{unread_notifications(current_user).length})", admin_comments_path
+                      %li= link_to 'See all Comments', admin_comments_path(anchor: 'all_comments')
       - else
         %ul.nav.navbar-nav.navbar-right
           - if CONFIG['authentication']['ichain']['enabled']
diff --git a/app/views/layouts/_user_menu.html.haml b/app/views/layouts/_user_menu.html.haml
index fe349b3b..1764d9d0 100644
--- a/app/views/layouts/_user_menu.html.haml
+++ b/app/views/layouts/_user_menu.html.haml
@@ -21,14 +21,15 @@
     = link_to(destroy_user_session_path, :method=>'delete') do
       %span.fa.fa-minus
       Sign out
-- if can? :manage, Conference
+- if can? :access, Admin
   %li.divider
     %li
-      = link_to(admin_conference_index_path()) do
-        - if Conference.any?
+      - if Conference.any?
+        = link_to(admin_conference_index_path()) do
           %span.fa.fa-home
-            Administration
-        - else
+          Administration
+      - if can? :create, Conference
+        =link_to(new_admin_conference_path) do
           %span.fa.fa-plus
           Create Conference
     -if @conference and @conference.id and can? :show, @conference
diff --git a/config/routes.rb b/config/routes.rb
index 5f8a59b6..05766f76 100644
--- a/config/routes.rb
+++ b/config/routes.rb
@@ -15,6 +15,7 @@ Osem::Application.routes.draw do
   namespace :admin do
     resources :users
     resources :people
+    resources :comments, only: [:index]
     resources :conference do
       member do
         get :roles
diff --git a/spec/controllers/admin/comments_controller_spec.rb b/spec/controllers/admin/comments_controller_spec.rb
new file mode 100644
index 00000000..ac75b189
--- /dev/null
+++ b/spec/controllers/admin/comments_controller_spec.rb
@@ -0,0 +1,59 @@
+require 'spec_helper'
+
+describe Admin::CommentsController, type: :controller do
+
+  # It is necessary to use bang version of let to build roles before user
+  let(:conference) { create(:conference) }
+  let!(:first_user) { create(:user) }
+  let!(:organizer_role) { create(:role, name: 'organizer', resource: conference) }
+  let(:organizer) { create(:user, role_ids: organizer_role.id, last_sign_in_at: Time.now - 1.day) }
+  let(:participant) { create(:user) }
+  let(:event) { create(:event, conference: conference) }
+  let(:comment) { create(:comment, commentable_type: 'Event', commentable_id: event.id) }
+
+  context 'not logged in user' do
+    describe 'GET #index' do
+      it 'renders the :index template' do
+        comment
+        get :index
+        expect(response).to redirect_to(user_session_path)
+      end
+    end
+  end
+
+  context 'logged in as admin, organizer or cfp' do
+    before :each do
+      sign_in(organizer)
+      comment
+    end
+    describe 'GET #index' do
+      it 'populates a hash with comments' do
+        get :index
+        expect(assigns(:comments)).to be_a(Hash)
+        # assigns(:comments).first returns an array of first pair key-value from hash.
+        # Calling again 'first' returns the key, meaning the Conference object.
+        expect(assigns(:comments).first.first.title).to eq(comment.commentable.conference.title)
+      end
+      it 'has status 200: OK' do
+        get :index
+        expect(response).to have_http_status(:ok)
+      end
+      it 'renders the :index template' do
+        get :index
+        expect(response).to render_template(:index)
+      end
+    end
+  end
+
+  context 'logged in with any other role or normal user' do
+    describe 'GET#index' do
+      it 'requires organizer privileges' do
+        sign_in(participant)
+        comment
+        get :index
+        expect(response).to redirect_to(root_path)
+        expect(flash[:alert]).to match('You are not authorized to access this area!')
+      end
+    end
+  end
+end
diff --git a/spec/factories/comments.rb b/spec/factories/comments.rb
new file mode 100644
index 00000000..a424e23b
--- /dev/null
+++ b/spec/factories/comments.rb
@@ -0,0 +1,9 @@
+# Read about factories at https://github.com/thoughtbot/factory_girl
+
+FactoryGirl.define do
+  factory :comment do
+    body 'Most interresting comment ever, created by a girl.'
+    user
+    association :commentable, factory: :event
+  end
+end
diff --git a/spec/factories/events.rb b/spec/factories/events.rb
index 537dfecb..6dc89b22 100644
--- a/spec/factories/events.rb
+++ b/spec/factories/events.rb
@@ -47,6 +47,7 @@ FactoryGirl.define do
         event.difficulty_level = build(:difficulty_level, conference: event.conference)
         event.track = build(:track, conference: event.conference)
         event.room = build(:room, conference: event.conference)
+        event.comment_threads << build(:comment, commentable: event)
       end
     end
 
diff --git a/spec/models/ability_spec.rb b/spec/models/ability_spec.rb
index b3859748..73812dc1 100644
--- a/spec/models/ability_spec.rb
+++ b/spec/models/ability_spec.rb
@@ -141,6 +141,8 @@ describe 'User' do
       it{ should_not be_able_to(:manage, other_event.difficulty_level) }
       it{ should be_able_to(:manage, event.commercials.first) }
       it{ should_not be_able_to(:manage, other_event.commercials.first) }
+      it{ should be_able_to(:index, event.comment_threads.first) }
+      it{ should_not be_able_to(:index, other_event.comment_threads.first) }
     end
 
     context 'when user has the role cfp' do
@@ -198,6 +200,8 @@ describe 'User' do
       it{ should_not be_able_to(:manage, other_event.difficulty_level) }
       it{ should be_able_to(:manage, event.commercials.first) }
       it{ should_not be_able_to(:manage, other_event.commercials.first) }
+      it{ should be_able_to(:index, event.comment_threads.first) }
+      it{ should_not be_able_to(:index, other_event.comment_threads.first) }
     end
 
     context 'when user has the role info_desk' do
@@ -255,6 +259,8 @@ describe 'User' do
       it{ should_not be_able_to(:manage, other_event.difficulty_level) }
       it{ should_not be_able_to(:manage, event.commercials.first) }
       it{ should_not be_able_to(:manage, other_event.commercials.first) }
+      it{ should_not be_able_to(:index, event.comment_threads.first) }
+      it{ should_not be_able_to(:index, other_event.comment_threads.first) }
     end
 
     context 'when user has the role volunteers_coordinator' do
@@ -312,6 +318,8 @@ describe 'User' do
       it{ should_not be_able_to(:manage, other_event.difficulty_level) }
       it{ should_not be_able_to(:manage, event.commercials.first) }
       it{ should_not be_able_to(:manage, other_event.commercials.first) }
+      it{ should_not be_able_to(:index, event.comment_threads.first) }
+      it{ should_not be_able_to(:index, other_event.comment_threads.first) }
       it 'should be_able to :manage Vposition'
       it 'should be_able to :manage Vday'
     end