Some of the species that are believed to have the highest probability of extinction are also amongst the most poorly known, and this makes it extremely difficult to decide how to spend scarce resources. Assessments of conservation status made on the basis of loss or degradation of habitat and lack of records may provide compelling indications of a decline in geographical range and population size, but they do not help identify where conservation action might be best targeted. Methods for assessing the probability of extinction and for modelling species’ distributions exist, but their data requirements often exceed the information that is available for some of the most urgent conservation cases. Here we use all available information (localities, expert information, climate and landcover) about a high-priority Vietnamese bird species (Edwards’s pheasant Lophura edwardsi) to assess objectively the probability of its persistence, and where surveys or other conservation action should be targeted. It is clear that the species is on the threshold of extinction and there is an urgent need to survey Bach Ma National Park (including the extension) and to consider surveying Ke Go Nature Reserve. This approach has potential to help identify where conservation action should be targeted for other Critically Endangered species for which there is an extreme scarcity of information.