High quality teachers are essential to improving the teaching and learning of mathematics and science, necessitating effective professional development (PD) and learning environments for teachers. However, many PD programs for science and mathematics teachers fall short because they fail to consider teacher background, experience, knowledge, beliefs, and needs (Loucks-Horsley, Love, Stiles, Mundry, & Hewson, 2003). To develop more effective PD systems, it is necessary to assess and identify teachers PD needs, expectations, experiences and constraints. In this manuscript, we describe the findings from a study that examined the PD experiences, needs, expectations, and constraints of middle and high school science and mathematics teachers in one state in the U.S. We examine similarities and differences between science and mathematics teachers and among teachers from urban, suburban and rural schools. The findings from this study suggest that mathematics and science teachers participate in a minimal amount of PD and that a number of factors contribute to this reality. Furthermore, science and mathematics teachers do not experience effective PD learning environments described by Bransford, Brown & Cocking (2000) and there is a mismatch between teachers PD needs and experiences. (Contains 11 tables.)