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Biodiversity theories are not very often explicitly consulted in conservation practice, but implicitly many conservation decisions rely on theory. Biodiversity theories can inform important conservation actions such as assessments of species richness and extinction or habitat loss and fragmentation. Popular examples of biodiversity theories are niche theory and island biogeography theory, whereas neutral theory is less known. Here, we review the implications of biodiversity theories for conservation practice, focusing on neutral theory. Neutral theory assumes that the establishment and success of an individual in a community does not depend on its species identity, but is instead predominantly driven by a stochastic process. We found that drift and stochasticity appear much less frequently in conservation studies than selection processes typical of niche theory. This might be because habitat-specificity is not supported by neutral theory, but is common among rare and vulnerable species. Furthermore, neutral theory makes less intuitive assumptions than niche theory and does not consider trophic interactions. However, models based on neutral theory proved to be useful in some biodiversity hotspots. Moreover, some models based on neutral theory subdivide space into local community and metacommunity, which reflects concepts commonly used in conservation science. Neutral approaches have been used in conservation to generate realistic species-abundance distributions and species-area relationships, provide a standard against which to compare species loss, prioritize species protection, model biological invasions, and support protected area design. We propose that neutral theory can serve as a valuable first-order approximation to reduce complexity and by design account for drift and stochasticity. Neutral theory provides the benefits of a community theory whereas niche theory focuses on single species. Ideally, neutral approaches should be used as a starting point for conscious stepwise addition of niche structure. This step-wise approach reflects recent integrative biodiversity theories that combine aspects of neutral and niche theory such as the stochastic niche or emergent neutrality and may provide a promising foundation for future conservation practice.