Cumulative impact assessment (CIA) has emerged as an approach for evaluating the combined environmental and social burdens disproportionately experienced by vulnerable communities. Such communities often face multiple overlapping stressors, including chemical exposures, poverty, lifestyle factors, psychosocial stress, underinvestment in infrastructure, and reduced healthcare access that interact to exacerbate health disparities. CIA differs from traditional risk assessment (RA) by emphasizing community-level characterization of combined and contextual stressors and prioritizing interventions rather than precise quantitative risk estimates; traditional RA was not designed to fully capture the cumulative, place-based nature of co-occurring stressors. CIA has therefore developed as a separate, coexistent framework that supports identification, prioritization, and mitigation of disproportionate community burdens. This analysis discusses the evolution of the CIA, tracing its policy drivers, definitional ambiguities, and the diversity of frameworks currently in use. We assess key scientific challenges and methodological considerations, including:

• stressor quantification,
• the role of stressor–response information in prioritization,
• integration of chemical and non-chemical factors,
• treatment of race and structural determinants, and
• participatory approaches that enhance local relevance and actionability.

We also examine regulatory and institutional factors that influence implementation, including statutory authorities and cross-sector coordination. Drawing on the literature and expert perspectives, we identify opportunities to strengthen CIA through improved transparency, data integration, flexible and context-appropriate methodologies, and meaningful stakeholder engagement. Advances in data science, causal inference, and structured decision-support tools such as multi-criteria decision analysis offer pathways to integrate diverse evidence streams while explicitly addressing uncertainty. We conclude that CIA applied as a screening and decision-support framework can be a policy-relevant tool for advancing equity through coordinated action among agencies, researchers, stakeholders, and communities. We provide recommendations, including necessary research, for CIA to continue to develop as a credible science-based and policy-relevant tool for reducing inequities and protecting public health.