Global biodiversity has been in decline for several decades, marked by species extinctions and population losses that have cascading negative impacts on ecosystems. Despite the growing list of described species, much of the actual threatened biodiversity remains unknown, particularly among invertebrates, including the ones with a parasitic mode of life. Parasites, which may outnumber free-living species and constitute a significant proportion of ecosystem biomass, have largely been overlooked in conservation efforts. The extinction of free-living host species often leads to co-extinction events, where dependent parasite species also face extinction. This chapter highlights the need to integrate parasite conservation into broader conservation science and management practices. It provides an overview of the evolution of species conservation from a focus solely on free-living species to one that includes associated parasitic species. A case study on chondrichthyan parasites illustrates the critical role of parasites in ecosystem health and the importance of their conservation. The chapter also outlines future research directions to better understand and conserve aquatic parasites, advocating for their inclusion in biodiversity monitoring programmes and conservation agendas. Addressing these gaps is essential for maintaining the integrity of natural systems and the biodiversity they support.