In response, policymakers, hospital systems, and industry leaders have increasingly turned to FDA-registered outsourcing facilities, commonly referred to as 503B compounding facilities, as a potential mitigation mechanism. Growth of outsourcing facilities: What the trend really showsSince the early post-DQSA years, the number of registered outsourcing facilities has grown steadily but modestly. Where outsourcing facilities have made a differenceThere is credible evidence that outsourcing facilities have played a supportive role in mitigating the clinical impact of some shortages, particularly in acute care settings. This explains why outsourcing facilities have not reduced the overall number, duration, or recurrence of drug shortages, even as they have mitigated harm in specific cases. Outsourcing facilities have reduced the clinical impact of some shortages, but they have not resolved the US drug shortage crisis.