Understanding sex and sexuality, particularly in the context of therapeutic work has been consistently identified as problematic. This qualitative study focused on the accounts of 8 counselling psychologists’ understanding and experiences of working with sex and sexuality. An interpretative phenomenological analysis was conducted and three master themes were identified. These highlighted how participants negotiated firstly, the influences of circulating cultural norms, in the past and present, secondly, the diverse presentations of sexuality and thirdly, the challenges of working therapeutically in relation to sex and sexuality. These negotiations and challenges were presented in their appraisal of their own personal lives; and in their training and professional experiences in client work. Participants’ developing confidence as practitioners seemed to be related to their capacity to re-evaluate their understandings of sexuality both personally and in relation to their therapeutic work. Overall, this research makes visible how a reflexive approach can inform counselling psychologists’ understanding that sex and sexuality are not static concepts and require continual questioning and revision.