Endocrine Self-Assessment Program (ESAP), Reference Edition 2021 is a self-study curriculum for physicians and health professionals wanting a self-assessment and a broad review of endocrinology. It consists of 120 brand-new multiple choice questions in all areas of endocrinology, diabetes, and metabolism. There is extensive discussion of each correct answer, a comprehensive syllabus, and references. ESAP is updated annually with new questions.