HIV voluntary counselling and testing (VCT) is now an integral part of many HIV care and control programmes. However, very little work has been done to assess the quality of VCT services. An evaluation of VCT services for mineworkers in Welkom, South Africa was conducted to assess client and counsellor satisfaction, the quality of the services and to identify barriers to uptake of VCT. A cross-sectional survey was carried out using tools developed by UNAIDS, consisting of semi-structured interviews and observation of counselling sessions. Twenty-two nurse counsellors and six community volunteers were interviewed. Twenty-four counselling sessions were observed and 24 client exit interviews were conducted. Although nine of the 22 nurse counsellors had only in-service rather than formal training for HIV counselling whereas all community volunteers had been formally trained, nurse counsellors demonstrated better interpersonal skills than did community volunteers. Both clients and counsellors identified fear of a positive result as a major barrier to HIV testing. Clients also raised concerns about confidentiality. UNAIDS evaluation tools were a feasible and an acceptable method of assessing VCT in this operational setting. The study identified areas where training needs to be strengthened and suggested ways of improving the services, and changes to the service have now been implemented in line with these recommendations.