Teacher collaboration is an increasingly important aspect of the professionalism of teachers: it is a way to reflect on and improve teaching practices. Teacher collaboration has been associated with teachers' professional growth and an increase in self-efficacy. However, policy makers and educational leaders must understand which structures of collaboration best lead to greater interdependence among teachers and to the development of collective efficacy. This quantitative study used Bandura's self-efficacy theory to explore how various forms of teacher collaboration and teacher participation in collaborative professional learning might be associated with teachers' perceptions of self-efficacy and collective efficacy in teaching elementary mathematics. Using survey data, this study analyzed potential relationships between teacher self-efficacy and collective efficacy and differences in self-efficacy and collective efficacy based on teaching experience. The data showed teacher self-efficacy and teacher collective efficacy were two distinct constructs. Therefore, efforts to increase teachers' self-efficacy might not necessarily translate into an increase of their collective efficacy in teaching elementary mathematics. This study also found teachers with 1-5 years of experience had statistically significant lower collective efficacy than other groups of teachers. The study offers several recommendations for how policy makers and school leaders can support the development of certain collaborative structures that could lead to successes and mastery experiences, which could, in turn, contribute to a sense of collective efficacy. The study also offers practical recommendations for proactively engaging new teachers in experiences that build collective efficacy and continuous professional growth. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://bibliotheek.ehb.be:2222/en-US/products/dissertations/individuals.shtml.]