If professional development relies on scripts and mandates rather than on learning communities and continuous improvement, it can actually hinder teachers' growth. The author expresses his fear that the teachers most likely to receive such inferior training are the ones who work with the student population most in need of high-quality teaching. The author points out that administrators who are responsible for professional development in schools would do well to heed the advice of VISA founder Dee Hock: "Have a simple, clear purpose which gives rise to complex, intelligent behavior, rather than complex rules and regulations that give rise to simplistic thinking and stupid behavior." Hock's admonition clarifies the authors concern that this nation is rapidly creating a two-tiered professional development system that ill serves a significant number of teachers and their students.