This book is highly recommended. It is an easy read, emphasising the importance of play not only in child development but also in determining how creative, innovative, successful, and happy we are as adults. It deals with play in terms of neuroscience and deals with how play changes the brain and shapes it. The existence of play can make mundane activities tolerable and even fun. Unstructured play enables children to figure out social roles and understand cause and effect. The argument here is that play is a primal need and is as important as sleep.