diff --git a/app/controllers/tasks_controller.rb b/app/controllers/tasks_controller.rb
--- a/app/controllers/tasks_controller.rb
+++ b/app/controllers/tasks_controller.rb
@@ -1,7 +1,6 @@
 class TasksController < ApplicationController
 
-  before_filter :authenticate
-
+  before_filter :authenticate, :check_viewability
 
   def index
     redirect_to :action => 'list'
@@ -12,4 +11,14 @@
     @user = User.find(session[:user_id])
   end
 
+  protected
+
+  def check_viewability
+    user = User.find(session[:user_id])
+    if user==nil or !Configuration.show_tasks_to?(user)
+      redirect_to :controller => 'main', :action => 'list'
+      return false
+    end
+  end
+
 end