The era of highly effective pre-exposure prophylaxis (PrEP) has transformed HIV prevention, yet global HIV incidence remains unacceptably high, particularly in sub-Saharan Africa. While antiretroviral-based prevention is critical, persistent structural barriers to access and adherence highlight the urgent need for a complementary preventive HIV vaccine. In this narrative review and perspective, we argue that scientific progress toward an HIV vaccine must be matched by equally ambitious preparedness investments across three domains: manufacturing and supply chains, clinical trial and regulatory infrastructure, and delivery systems and community engagement. Drawing on lessons from the global rollout of PrEP, post-exposure prophylaxis (PEP), and the COVID-19 pandemic response, we outline a five-pillar strategic roadmap. This roadmap focuses on ensuring that a future HIV vaccine reaches the people who need it most from the moment of regulatory authorization, calling for co-investment in diverse platforms, binding advance market commitments, logistical simulation, and proactive planning for post-licensure effectiveness trials. Preparedness is not secondary to science; it is its essential partner.