To make services more accessible, acceptable and affordable, sexual health service delivery models have embraced innovation, technology, outreach and decentralisation. In particular, some routine high-volume services, like asymptomatic testing for sexually transmitted infections (STIs), can be delivered in general practice, online or in non-clinical settings. On the surface, sexual health clinics, like hospitals or other primary care clinics, might appear to be operating on a model that has not changed significantly in recent times. However, globally sexual healthcare needs are rising both in volume and complexity, not all of which can be adequately met through decentralised care. Sexual health clinics themselves are the site of considerable innovation. The importance of sexual health clinics in the diagnosis and treatment of symptomatic STIs is likely to increase with the increasing burden of disease, the complexity of treatment guidelines and the emergence of new infections. Services essential to patient health such as immediate or complex clinical care, partner notification and safeguarding, and activities essential to the health system like research, training and supervision require expertise to be located where it can be accessed and maintained at reasonable cost. We do not know whether increasing some services outside existing models can safely compensate for reducing other services inside them.