At a time when many older facilities are being decommissioned and many more are undergoing major retrofits to extend their lives, there is a wealth of information emerging to guide the design of new facilities, to make them easier to rebuild and eventually decommission. In this publication, the most important lessons learned in recent years are organized and examined to enable the intended audience to gauge the importance of this aspect of planning for new nuclear facilities. With many new players entering the nuclear field, whether as customers or suppliers, it is important that the lessons learned on this issue be widely and promptly disseminated. This publication presents the issues in a concise and systematic manner, along with practical and thought provoking examples.