The syndemic of HIV, sexually transmitted infections (STIs), and early pregnancy remain a key challenge to global public health. Decision-making around sexual and reproductive health (SRH) behaviours is critical to ensuring the uptake of biomedical technologies. Drawing from behavioural science theories, we propose a novel conceptual frameworkâ??the Decision Cascadeâ??to describe the decision-making process that a user will go through as they navigate these decisions. Analogous to the HIV prevention and treatment cascade, this model describes key steps individuals go through when deciding to use HIV prevention technologies. Each step (being cued/triggered to act, reacting to the behaviour, evaluating the behaviour, assessing the feasibility of acting and the timing and final execution of the action), is influenced by a myriad of individual and socio-cultural factors, shaping the ultimate decision and behaviour outcome in a continual cycle. This framework has applications beyond HIV prevention, extending to other SRH technologies and treatments. By prioritizing human-centered design and understanding user decision-making intricacies, interventions can enhance effectiveness and address the complexities of SRH service uptake across diverse populations. The Decision Cascade framework offers a comprehensive lens to inform intervention design, emphasizing the need for nuanced approaches that resonate with the realities of decision-makers. Adopting such approaches is essential to achieving meaningful impact in HIV prevention and broader SRH initiatives.