Insecticides are the most common management tool for Colorado potato beetle (Leptinotarsa decemlineata) infestations in Croatian potato. After decades of insecticide reliance, Colorado potato beetles throughout the country have developed varying levels of resistance to multiple insecticide modes of action. As a result, growers are dependent on broad spectrum insecticides that have significant negative impacts for human health and the environment. This project is a new collaboration between the University of Zagreb and my program to better understand the spatiotemporal patterns of insecticide resistance throughout the major vegetable producing areas of Croatia. We have leveraged existing bioassay data generated by colleagues in Croatia to identify where problematic Colorado potato beetle populations occur. Deliverable outcomes of this project will facilitate targeted extension messaging about Insecticide Resistance Management (IRM) and alternative Integrated Pest Management (IPM) activities to stem the negative consequences additional pesticide use.