We first conducted a synthesis of literature to identify essential transition teacher competencies to guide curriculum development for a personnel preparation program. The synthesis yielded a list of 67 competencies needed by transition teachers. Using the 67 competencies, we next created an electronic survey in which respondents were asked to rate importance of transition teacher competencies. The survey was administered to two groups: national experts and transition practitioners. Expert respondents were 52 individuals. Practitioner respondents were 231 teachers, specialists, or coordinators from five states. Results indicated substantial similarities in ratings across all respondents irrespective of sample membership or service to transition-age individuals with mild/moderate or severe disabilities. Findings are discussed in regard to personnel preparation and targeted knowledge and skills.