According to Directive 1107/2009 of the EU our department is officially recognized as a facility for efficacy testing of plant protection products. We are thus holding a GEP (good experimental practice) Recognition Certificate, authorized from the German Plant Protection Service. Over the years, we have gained huge experience in conducting field trials in particular in viticulture, testing various aspects of integrated and biological control of grapevine pests and diseases. In field and greenhouse trials, we are testing plant protection products and/or agents for their efficacy, selectivity and (un)desired side effects, focusing on the best application date and interval, screening for the optimal concentration of active ingredients, taking fungicide resistance aspects into consideration and optimizing newly developed biological control agents (e.g. application coat, uptake by fungal cells, rain stability).