The presentation of a painful leg in primary and urgent care has many possible differentials. It is essential that clinicians take a structured and comprehensive approach to assessment, including history-taking and face-to-face physical examination to ensure that nothing is missed (Armstrong, 2020). This article is not intended as a substitute for practical learning in physical assessment and history-taking, but rather it serves as an aide memoire for those who are still developing these clinical skills.The possible differentials of painful legs — whether upper or lower, unilateral or bilateral — are discussed, looking at key areas such as clinical presentation, correct assessment and history-taking, red flags, relevant investigations, and an introduction to treatment options. References to resources available, e.g. national guidelines, are also provided.