This concise primer focuses on systems thinking as it spans the domains of health administration, public health, and clinical practice. Currently, the accrediting commissions within public health, health administration, and nursing are including systems thinking as part of the core competencies in their respective fields and professions. Meanwhile, academic programs do not have the materials, other than journal articles, to give students the requisite understanding of systems thinking as is expected of the next generation of health professionals. Health Systems Thinking:  A Primer is designed to meet that void and serve as a supplemental reading for this important and timely topic.