According to the 2014–2015 State of the States in Gifted Education, Colorado is the only state in the United States where a series of onsite, customized twice-exceptional professional development opportunities have been implemented. Yet, the Colorado Department of Education and its partner school districts have not systematically evaluated the impact of that two-year initiative. The purpose of this study was to understand the implementation of twice-exceptional professional development during 2014–2016 in a school district in Colorado. A case study design was used to better understand (a) educators’ perspectives about their training experiences and the educational services developed and/or implemented as a result of the training, (b) educators’ perceptions of the training’s impact on twice-exceptional students’ learning, and (c) organizational support and changes that facilitated the implementation of twiceexceptional educational services. Seven training participants and four administrators who were involved in the training were purposefully selected. Documentation and archival records were collected, and interviews were conducted. Eight major themes emerged: (a) increased knowledge and skills, (b) evolved attitudes, (c) recurring challenges, (d) utilizing a team approach, (e) improved performance, (f) difficulty in measuring impact, (g) improved school culture, and (h) planning for the future. In addition to a discussion of themes, implications for improving educator and student outcomes and for creating organizational support and changes are presented. This study contributes to educational research and evaluation in order to assist a local education agency in designing, implementing, and evaluating professional development that provides educators of twice-exceptional students with the knowledge and skills necessary to enable students to succeed in their education
