This seems to be an ever returning question in Joomla world, you might already read the first part of the sequel: How to reuse Joomla 1.0 templates?. So, let's go one step further, and let's see how we can easily reuse those nice Joomla 1.5 templates in the post-Joomla 1.7 world (more specifically under Joomla 2.5). Don't expect a fully covering guide on how to convert Joomla 1.5 template to Joomla 2.5 template, but instead a detailed description on what I usually do - less theory, more practical knowledge.