BackgroundThe African Health Professions Regulatory Collaborative (ARC) was launched in 2011 to support countries in East, Central, and Southern Africa to safely and sustainably expand HIV service delivery by nurses and midwives. While the World Health Organization recommended nurse initiated and managed antiretroviral therapy, many countries in this region had not updated their national regulations to ensure nurses and midwives were authorized and trained to provide essential HIV services. For four years, ARC awarded annual grants, convened regional meetings, and provided technical assistance to country teams of nursing and midwifery leaders to improve national regulations related to safe HIV service delivery. We examined the impact of the program on national regulations and the leadership and organizational capacity of country teams.MethodsData was collected to quantify the level of participation in ARC by each country (number of grants received, number of regional meetings attended, and amount of technical assistance received). The level of participation was analyzed according to two primary outcome measures: 1) changes in national regulations and 2) improvements in leadership and organizational capacity of country teams. Changes in national regulations were defined as advancement of one “stage” on a capability maturity model; nursing and midwifery leadership and organizational capacity was measured by a group survey at the end of the program.ResultsSeventeen countries participated in ARC between 2012 and 2016. Thirty-three grants were awarded; the majority addressed continuing professional development (20; 61%) and scopes of practice (6; 18%). Fourteen countries (representing approximately two-thirds of grants) progressed at least one stage on the capability maturity model. There were significant increases in all five domains of leadership and organizational capacity (p < 0.01). The number of grants (Kendall’s tau = 0.56, p = 0.02), duration of technical assistance (Kendall’s tau = 0.50, p = 0.03), and number of learning sessions attended (Kendall’s tau = 0.46, p = 0.04) were significantly associated with improvements in in-country collaboration between nursing and midwifery organizations.ConclusionsThe ARC program improved national nursing regulations in participating countries and increased reported leadership, organizational capacity, and collaboration among national nursing and midwifery organizations. These changes help ensure national policies and professional regulations underpin nurse initiated and managed treatment for people living with HIV.Electronic supplementary materialThe online version of this article (10.1186/s12913-018-3233-4) contains supplementary material, which is available to authorized users.