Current and future agricultural practices have to address a number of challenges, including increasing crop productivity and applying environmentally sensitive methodologies under conditions of climate change. In this context, the use of fungal metabolites is emerging as a strategy for ensuring agricultural and environmental sustainability while feeding the world’s growing population. In this chapter, we discuss the role of fungal phytopathogens as a source of metabolites for different agricultural applications. Particular attention is given to volatile compounds and cell-free filtrates as sources of bioactive metabolites. The application of fungal phytopathogen metabolites to promote plant growth, mitigate biotic and abiotic stresses, and provide a source of natural herbicides for weed control, are all considered, as are future perspectives. A review of the literature related to this field is presented, providing a comprehensive overview of our current understanding.