Significant increases in genitourinary (GU) medicine clinic workloads throughout the UK have resulted in an unmet demand for appointments, and increased waiting times. In order to meet the government target of a 48-hour maximum waiting time for all patients, many clinics are modernising current practices to increase capacity and improve access to services. The 'Six Sigma' study group of 12 GU medicine clinics which was formed in 2003 to investigate means of enhancing capacity of GU medicine services, has demonstrated that there is a significant amount of unreleased capacity within UK clinics. In this article, the Six Sigma group present potential actions which other GU medicine clinics in the UK may be able to apply and thereby release additional capacity. Example case studies from the Six Sigma study are also presented, illustrating the applicability of this model throughout the UK. The findings of the Six Sigma project offer GU medicine clinics across the UK the opportunity to increase capacity, without adversely affecting quality of care.