Introduction Obesity and Related Comorbidities Mechanisms Underlying Food Intake and Obesity Mechanisms Underlying Obesity-Related Comorbidities Drugs to Treat Obesity Investigational Obesity Drugs and Points of Drug Intervention Obesity Platform-Based Drug Discovery Alliances Directions in Obesity R&D Outlook Table 1. Select Targets That Regulate Appetite Table 2. Select Obesity Drugs in Clinical Trials Table 3. Select Drug Targets That Regulate Lipid Metabolism Table 4. Select Drug Targets That Regulate Adipocytes or Their Signals Table 5. Select Drug Discovery Alliances Targeting Obesity Figure 1. Systems Involved with Controlling Appetite Figure 2. Metabolic Pathways and Enzymes Involved in the Synthesis of Fat and Fatty Acids