Abstract The social identity approach was used to explore the inter-professional relations between nurse prescribers, pharmacist prescribers and general practitioners (GPs) in primary care in the United Kingdom. We investigated their social identities as prescribers, the influence of social structure in practice settings and the implications for further development of nurse and pharmacist prescribing. Interviews were conducted with 21 GPs, nurse prescribers and pharmacist prescribers in primary care from the south of England. Five themes emerged, including the ambiguous social identity of some nurse and pharmacist prescribers (‘a no man’s land’), constraining social structures (‘the doctor is king’), the content of GPs’ social identity (‘subtle prescribing’), the content of nurse and pharmacists’ social identity (‘more than just competent’) and context (‘engaging with each other’s identities’). At some GP practices, there was a willingness to engage with the different social identities and reframe them within the organisational context of a GP surgery. At these sites, where social identities were respected and supported, the social identity approach offered insight into how the resulting teamwork could lead to a shared practice identity focused on multi-disciplinary working. This research provides evidence of how professional and organisational identities can be enhanced and supported. Further, there is the potential for an intervention using the social identity approach to improve patient care.