“Aha moments” are sudden creative insights that convey breakthrough ideas and new perspectives. They enrich our lives and empower personal and professional success.  How do they happen?  When do you need them?  How can you have more of them?  A new book by John Kounios and Mark Beeman, the cognitive neuroscientists who discovered how the brain has these eureka experiences, explains both the principles underlying creative insight and practical strategies for its enhancement.