Addressing community-level factors (CLFs) is integral to the ongoing effort to design multilevel, effective, and sustainable interventions to address each element of the HIV/AIDS treatment cascade. This review, the first critical review of this topic, identified 100 articles that (1) assessed CLFs in relation to the HIV/AIDS treatment cascade, (2) had been peer-reviewed, and (3) were based on studies conducted in low- or middle-income countries. Social support and social networks, cultural norms, gender norms, and stigma were the key CLFs associated with treatment and care. This extensive review found only 5 evaluations of interventions designed to affect CLFs, reflecting a major gap in the literature. All were communication interventions designed to create a more positive environment for HIV testing and access to treatment and care, thus pointing to some of the potential extraindividual effects of communication interventions. The qualitative data are rich and vital for understanding the context; yet, more quantitative analysis to provide evidence regarding the distribution of these factors is essential, as only 19 of the studies were quantitative. There is a pressing need to (1) collect community-level data, (2) validate social and gender norm scales, and (3) better use available data regarding social norms, gender norms, and other CLFs. These data could be aggregated at the cluster, neighborhood, or community levels and incorporated into multilevel analysis to help clarify the pathways to enhanced outcomes across the treatment cascade and thereby mitigate HIV sequelae.