The use of temporary, or locum, clinical staff during staffing shortages may introduce process and teamwork challenges and lead to errors. This qualitative study examined a wide range of perspectives on the use of locum doctors in the United Kingdom’s National Health Service (NHS). The study identified five themes centered on familiarity, service consistency, acceptance, overuse as a protective strategy, and administrative gaps – all of which challenge patient safety. The authors call for organizations and locums to collaborate on policies to support effective integration of this workforce population.