Executive SummaryIdentifying means of assisting teachers in integrating technology during their instruction is becoming more important as the rate new technologies enter the classroom accelerates. The primary means of helping in-service teachers employ new technologies in their classrooms is frequently professional development. Unfortunately, professional development offered to many teachers is ineffective. It has been posited that professional development can be made more effective by emphasizing one specific technology for an extended period of time, including opportunities for teachers to learn from each other in localized contexts, and organizing the learning in ways calculated to help teachers build technology self-efficacy (DeSantis, 2012). This paper shares the results of a research project conducted to determine if professional development with these attributes assists teachers with developing the skills required to integrate technology during instruction. This project involved the creation of a professional development program with the characteristics described in the literature as being most effective (Brinkerhoff, 2006;Cantrell & Hughes, 2008;DeSantis, 2012;Doppelt et al., 2009;Walker et al., 2011). This mixed-methods and design-based study identifies changes in technology self-efficacy and technological, pedagogical, and content knowledge among forty-one teachers following their participation in sustained, collaborative, and scaffolded professional development for one rapidlyembraced technology, the interactive whiteboard. The possession of technology self-efficacy assists teachers in adopting new technologies (Brinkerhoff, 2006;Holden & Rada, 2011;Tschannen-Moran & McMaster, 2009;L. Wang, Ertmer, & Newby, 2004). Technological, pedagogical, and content knowledge are indicators of teachers' abilities to utilize educational technologies during instruction (Mishra & Koehler, 2006).The results of this study indicate that teachers who participate in well-designed professional development are likely build technology self-efficacy and technological, pedagogical, and content knowledge. Qualitative analysis of semi-structured participant interviews conducted with a random sample of participants in the study revealed that the professional development program under study was integral in this development. Participants were particularly affected by the opportunities to collaborate embedded within the professional development offering under study during this project. The results from thisMaterial published as part of this publication, either on-line or in print, is copyrighted by the Informing Science Institute. Permission to make digital or paper copy of part or all of these works for personal or classroom use is granted without fee provided that the copies are not made or distributed for profit or commercial advantage AND that copies 1) bear this notice in full and 2) give the full citation on the first page. It is permissible to abstract these works so long as credit is given. To copy in all other cases or to r...