The current biodiversity crisis is characterized by the decline and extinction of numerous animal populations and species world-wide. To aid in understanding the threats and causes of population decline and the assessment of endangerment status of a species, conservation scientists and practitioners are increasingly relying on remote assessments using biotelemetry (radio telemetry, acoustic telemetry, satellite tracking) and biologging (archival loggers) or hybrid technologies (e.g. pop-up satellite tags). These tools offer increasingly sophisticated means (e.g. large-scale telemetry arrays, fine-scale positioning, and use of physiological and environmental sensors) of evaluating the behaviour, spatial ecology, energetics, and physiology of free-living animals in their natural environment. Regional, national, and international threat assessments (e.g. the International Union for the Conservation of Nature [IUCN] Red List) require basic knowledge of animal distribution, emigration, behaviour, reproductive potential, mortality rates, and habitat use, which in many cases can all be obtained through biotelemetry and biologging studies. Such studies are particularly useful for understanding the basic biology of animals living in harsh environments (e.g. polar regions, aquatic environments), for rapidly moving or cryptic animals, and for those that undertake large-scale movements/migrations (e.g. birds, insects, marine mammals and fish). The premise of this paper is that biotelemetry and biologging have much to offer and should be embraced by the conservation science community to aid in assessment of threats and endangerment status. It is crucial that studies on endangered species must not further contribute to species decline or retard recovery. As such, there are complicated ethical and legal considerations that must be considered prior to implementing tracking studies on endangered wildlife. Furthermore, as many endangered animal species occur in developing countries, there is a need to develop capacity (financial support for the research and technical telemetry skills) for designing and conducting tracking studies. To stem the loss of biodiversity and aid in the recovery of endangered animal populations, there is a need for innovative and interdisciplinary research, monitoring programs and research initiatives to inform decision makers. It is clear that biotelemetry and biologging are not a panacea; however, they are valuable tools available to conservation practitioners. Used appropriately, biotelemetry and biologging have the potential to provide data that is often unattainable using other techniques, and can reduce uncertainty in the assignment of conservation status.