Peter Caley has worked widely in Australia and New Zealand applying quantitative methods to address contemporary problems caused by invasive species. This has included research into agricultural pest and pathogen introduction rates and detection probabilities, evaluating and developing models for screening invasive plants, predicting the future number and distribution of introduced species, and the development of methods for evaluating eradication progress including outbreak delineation. Other projects include managing vertebrate pests (e.g. wild pigs in the Northern Territory and their possible role in foot-and-mouth disease spread) and directly transmitted pathogens (e.g. pandemic influenza transmission in humans, bovine tuberculosis in New Zealand wildlife and livestock). In his current CSIRO Data61 role his projects include developing methods for evaluating the success of pest eradication programs, undertaking port-based risk assessments for the introduction of destructive Varroa mites of honey bees and tramp ants, developing models for assessing biofouling risk of international ships and evaluating the contribution of citizen science to biosecurity outcomes.