I do like Core Data but I realize that many people don't. In this blog post I would like to write about concurrency and performance, clear some things up and lay the foundation for successive posts in this series. Of course you should take my enthusiasm about Core Data with a grain of salt since I am the developer of Core Data Editor. That being said I think that Core Data needs more than just a defense of its potential flaws: A lot of explaining has to be done. Let's get dirty!