The book gives readers a practical introduction to reactive programming with Actor Model. The reader is given a brief but detailed background on using the Scala programming language and how to program using Scala and the Akka toolkit. After covering the basics and establishing a foundation, the book takes readers through a series of message-based integration cookbook solutions, including: Messaging Systems, Messaging Channels, Message Construction, Message Routing, Message Transportation, Message Endpoints, and System Management. The book follows the proven method presented in "Enterprise Integration Patterns" by Gregor Hohpe and Bobby Woolf, but gives solutions based on the use of Scala and Akka.