How divergent is this population? Where are the boundaries between populations of this species? These types of questions are often asked in the context of listing, de-listing or development of recovery plans for threatened or endangered species. However, understanding populationand divergence has relevance for informing management of any species. In order to preserve genetic diversity or a species' evolutionary legacy, it is necessary to know how genetic resources are distributed across the species' range. For example, managers often want to protect distinct populations, but it is important to determine whether such distinctions are based on recent processes such as bottlenecks or long-term isolation. We have worked on a number of projects assessing the distinctiveness of endemic species. Similarly, we use genetic information to estimate the level of migration or gene flow among populations to understand processes such as dispersal. By providing this information to managers, we aim to facilitate scientifically defensible decision making by our agency and our partners.