Ken Auer is the founder and president of RoleModel Software, one of the world's first companies dedicated to XP. He is well-known for his expertise in the practical application of object technology, and has been a frequent speaker and tutorial and workshop leader at various industry conferences for nearly fifteen years. He has published articles in numerous magazines (including Communications of the ACM) and is a contributing author to the Pattern Languages of Program Design series published by Addison-Wesley. Roy Miller is a software developer at RoleModel Software. He has been developing software and managing software projects for more than seven years. He has published articles and papers on Java and XP on IBM's developerWorks Web site and elsewhere, and speaks at conferences about how organizations can apply XP to increase competitive advantage.