BACKGROUND:: We describe promotional strategies for couples' voluntary HIV counseling and testing (CVCT) and demographic risk factors for couples in Lusaka, Zambia, where an estimated two thirds of new infections occur in cohabiting couples. PRINCIPAL FINDINGS:: CVCT attendance as a function of promotional strategies is described over a 6-year period. Cross-sectional analyses of risk factors associated with HIV in men, women, and couples are presented. Community workers (CWs) recruited from couples seeking CVCT promoted testing in their communities. Attendance dropped when CW outreach ended, despite continued mass media advertisements. In Lusaka, 51% of 8500 cohabiting couples who sought HIV testing were concordant negative for HIV (MF) and 26% concordant positive (MF); 23% had 1 HIV-positive partner and one HIV-negative partner, with 11% HIV-positive man/HIV-negative woman (MF) and 12% HIV-negative man/HIV-positive woman (FM). HIV infection was associated with men's age 30 to 39, women's age 25 to 34, duration of union <3 years, and number of children <2. Even among couples with either 1 or 2 or no risk factors, HIV prevalence was 45% and 29%, respectively. CONCLUSIONS:: Many married African adults do not have high-risk profiles, nor realize that only 1 may be HIV positive. Active and sustained promotion is needed to encourage all couples to be jointly tested and counseled.