Martin Odersky is the creator of the Scala language. He is a professor at EPFL in Lausanne, Switzerland, and a founder of Scala Solutions Inc. He works on programming languages and systems, more specifically on the topic how to combine object-oriented and functional programming. Since 2001 he has concentrated on designing, implementing, and refining Scala. Previously, he has influenced the development of Java as a co-designer of Java generics and as the original author of the current javac reference compiler. He is a fellow of the ACM. Lex Spoon is a software engineer at LogicBlox, Inc. He worked on Scala for two years as a post-doc at EPFL. He has a Ph.D. in computer science from Georgia Tech, where he worked on static analysis of dynamic languages. In addition to Scala, he has worked on a wide variety of programming languages, ranging from the dynamic language Smalltalk to the scientific language X10 to the logic language that powers LogicBlox. He and his wife currently live in Atlanta with two cats, a chihuahua, and a turtle. Bill Venners is president of Artima, Inc., publisher of the Artima Developer website (www.artima.com). He is author of the book, Inside the Java Virtual Machine, a programmer-oriented survey of the Java platform's architecture and internals. His popular columns in JavaWorld magazine covered Java internals, object-oriented design, and Jini. Active in the Jini Community since its inception, Bill led the Jini Community's ServiceUI project, whose ServiceUI API became the de facto standard way to associate user interfaces to Jini services. Bill is also the lead developer and designer of ScalaTest, an open source testing tool for Scala and Java developers.