This paper addresses the considerable interest there is in how to detect design patterns in existing designs and implementations. These approaches typically look for similarities between the diagrams used to describe the design and those which define the pattern. We look at several pattern detection techniques, before implementing and comparing two of the most successful. From this we conclude that both of these techniques have a certain ability to detect design patterns at the high levels of abstraction and programming language independence, needed at the design level. We then show that these approaches can work together to improve detection rates. Finally we propose how this work can be extended to detect more patterns and to include detection of anti-patterns.