Introduction: Building on earlier works demonstrating the effectiveness and acceptability of provider-initiated counselling and testing (PITC) services in integrated outpatient departments of urban primary healthcare clinics (PHCs), this study seeks to understand the relative utility of PITC services for identifying clients with early-stage HIV-related disease compared to traditional voluntary testing and counselling (VCT) services.We additionally seek to determine whether there are any significant differences in the clinical and demographic profile of PITC and VCT clients. Methods: Routinely collected, de-identified data were collated from two cohorts of HIV-positive patients referred for HIV treatment. either from PITC or VCT in seven urban-integrated PHCs. Univariate and multivariate analyses were conducted to compare the two cohorts across demographic and clinical characteristics at enrolment. Results: Forty-five per cent of clients diagnosed via PITC had CD4B200, and more than 70% (i.e. two thirds) had CD4B350 at enrolment, with significantly lower CD4 counts than that of VCT clients (pB0.001). PITC clients were more likely to be male (p=0.0005) and less likely to have secondary or tertiary education (pB0.0001). Among those who were initiated on antiretroviral therapy (ART), PITC clients had lower odds of initiating treatment within four weeks of enrolment into HIV care (adjusted odds ratio, or AOR: 0.86; 95% confidence interval, or CI: 0.75=0.99; p=0.035) and significantly lower odds of retention in care at six months (AOR: 0.84; CI: 0.77=0.99; p=0.004). Conclusions: In Lusaka Zambia, large numbers of individuals with late-stage HIV are being incidentally diagnosed in outpatient settings. Our findings suggest that PITC in this setting does not facilitate more timely diagnosis and referral to care but rather act as a ''safety net'' for individuals who are unwilling or unable to seek testing independently. Further work is needed to document the way provision of clinic-based services can be strengthened and linked to community-based interventions and to address socio-cultural norms and socio-economic status that underpin healthcare-seeking behaviour. Copyright: © 2012 Piloya T et al; licensee International AIDS Society.