Emerging contaminants (ECs) represent a growing environmental concern due to their persistence, toxicity, and potential to disrupt aquatic ecosystems. This chapter reviews the relationship between benthic macroinvertebrates and ECs, focusing on the most studied organisms, the types of contaminants, and the main effects reported. Bivalves, gastropods, crustaceans, and aquatic insects are the primary groups used in ecotoxicological studies due to their ecological relevance, widespread distribution, and ability to act as bioindicators. However, the predominance of laboratory studies over field investigations limits the understanding of EC impacts under natural conditions. Most research has concentrated on sublethal effects, such as physiological, biochemical, and immunological responses, which highlight the importance of studying ECs beyond lethality, as many contaminants do not induce direct mortality even at high concentrations. The lack of standardized methodologies for measuring ECs, variability in experimental protocols, and underrepresentation of certain macroinvertebrate groups indicate significant gaps in current knowledge. This underscores the need for harmonized approaches and an increased focus on field studies to better evaluate the ecological risks associated with ECs. Expanding research to less studied species and adopting multi-biomarker approaches will enhance our understanding of the complex effects of ECs on aquatic ecosystems, ultimately guiding more effective environmental management and policy development.