“…A large body of research has shown that district and school PD efforts can result in changes in teachers' knowledge and beliefs as well as in their instructional practice (Loucks-Horsley and Matsumoto, 1999). Some researchers have even found direct effects on student achievement for some types of PD (Huffman, Thomas, and Lawrenz, 2003). In contrast, the lack of human capitalincluding insufficient staffing and limited staff commitment, knowledge, and skillscan hinder efforts to implement wide-scale reform (Burch and Spillane, 2004;Elmore and Burney, 1999;Massell and Goertz, 1999;Firestone, 1989;Spillane and Thomp-son, 1997).…”