School-based agricultural education (SBAE) programs have become more diverse with the ever changing and growing agriculture industry. Agricultural education teachers are challenged with expanding their knowledge and competencies to effectively teach and design successful SBAE programs. Needs assessments aid in providing guidance for professional development to better equip teachers with adequate knowledge, experiences, resources and materials. To better understand how agricultural education teacher's needs have changed or remained the same, this synthesis provided insight into teacher needs assessments from 1983 to 2015. While some competencies revealed inconsistent results, several competencies produced overwhelmingly cohesive results. Findings indicated Computer Technology, Program Administration, Public Relations, FFA/Program Management, Managing Student Behavior, and Development and Supervision of SAE projects as consistent needs of agricultural education teachers. Less emphasis was needed in professional development in technical skills related to the AFNR career pathways. A variation of needs between experienced and beginning teachers has existed. Recommendations included addressing emerging needs in 21st century competence and working with special needs. To emphasize content focus, development of a consistent instrument to assist teacher educators and national organizations with designing professional development opportunities to meet the current needs of agricultural education teachers in all stages of their careers was recommended.