A Study of Retatrutide (LY3437943) in Participants With Obesity or Overweight

Inclusion Criteria: * Have a body mass index (BMI) of: * ≥30 kilogram per square meter (kg/m2) OR * ≥27 kg/m2 with at least one of the following weight-related conditions: high blood pressure, abnormal levels of lipid, obstructive sleep apnea, heart disease * Have at least one unsuccessful attempt to lose weight by dieting Exclusion Criteria: * Have a self-reported change in body weight \>5 kg (11 pounds) within 90 days before screening * Have a prior or planned surgical treatment for obesity * Have type 1 diabetes or type 2 diabetes * Have a family or personal history of medullary thyroid carcinoma (MTC) or multiple endocrine neoplasia syndrome type 2 (MEN-2) * Have had within the past 90 days before screening * acute myocardial infarction * cerebrovascular accident (stroke) * hospitalization for unstable angina, or * hospitalization due to congestive heart failure * Have New York Heart Association Functional Classification Class IV congestive heart failure * Have a history of chronic or acute pancreatitis * Have taken weight loss drugs, including over-the counter medications within 90 days prior to screening