Relationship between teacher efficacy and professional development in international schools of China was a quantitative experimental study that determined the correlation between professional development attendance and teachers' sense of self-efficacy. Supporting this data was a secondary investigation to determine if changes in teachers' sense of self-efficacy correlated to changes in student achievement. Teacher survey responses and student achievement scores were used to answer the research questions. The results of this study showed a significant positive correlation between teachers' sense of self-efficacy and attending a professional development event and showed a significant positive correlation between changes in teachers' sense of self-efficacy and increased student achievement. The benefit of this study was that professional development does have a positive effect on teachers' sense of self-efficacy and that these positive changes in self-efficacy have a positive effect on student achievement scores. [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://www.proquest.com.bibliotheek.ehb.be/en-US/products/dissertations/individuals.shtml.]