The release of the JPA 2.0 specification heralded a wider array of functionality and a more advanced feature set. This made some developers jump for joy at the prospect of being able to do more and still be compliant with the specification. The problem is that the standard doesn’t often come with a detailed instruction booklet describing when to use the new features, or the specific problems they were meant to solve. For the most part, developers must decide for themselves how and under what circumstances they will apply a given feature to their applications. We will discuss what the new features are and when they should be applied, as well as the conditions that could lead to their misuse. We will offer tips on what the most useful features are and explore some of the more puzzling parts.