When I have implemented CiviCRM for various clients I have always set it up on its own server. One of my clients saw some benefits in having it run on their website server - partly economics - and so it was moved. And then the problems started...one problem was conflicts with the many Drupal modules on the website which broke various bits of Civi. So my conclusion is that it's better to run Civi on a dedicate server where the environment can be controlled & suited to Civi. What do others think? What are the pros and cons?