Richard Skolnik, lecturer at Yale and author of the Essentials of Global Health textbook, explains what a health system is and how to judge its performance. He introduces the idea of value for money in health spending, then compares how countries structure their health systems, from financing to service delivery. The lecture surveys common problems these systems face, including cost, coverage gaps, and inconsistent quality, and discusses approaches that have proven cost-effective in addressing them. Drawn from Skolnik's Coursera course on global health, this module is aimed at students new to health systems thinking rather than specialists, and it stays at the level of organizing concepts and illustrative examples rather than deep country case studies. It runs eighteen minutes and functions as an orientation lecture within a larger course sequence on global health fundamentals.