Abstract: The goal of this two-year project is development of environmentally benign methods for controlling potato pathogens. Emphasis has been on late blight (P. infestans). During year 1, in-vitro screening assays against P. infestans and Erwinea carotovora (a bacterial pathogen) identified candidate control agents. Focus was on essential oil components (e.g. active A and active B) since these are generally recognized as safe (GRAS status). Other compounds and some microorganisms were also tested. Since some promising compounds were too volatile to be used in practice, they were formulated using 3M's controlled release technologies. During year 2 formulations were tested to ensure they did not adversely affect plant growth. None did. Testing for control of P. infestans on leaves continued. Some formulations conferred good protection, but not for long enough to be practical. Formulations were also tested for their abilities to protect stored tubers against P. infestans and E. carotovora. One of the active A formulations gave complete control of P. infestans, the duration of protection depending upon the amount of product used. In small scale tests protection extended at least 3 months. The formulation also gave complete, reversible suppression of sprouting.