Although their role in plant health management is still quite modest, ever increasing expectations are placed on biocontrol agents for the complementation or replacement of pesticide use. Despite decades of research and more than 12,000 scientific papers on biological control of plant diseases, little more than 14 microbe-based commercial products are presently registered for use against diseases in the European Union. Through a review of published scientific literature, economic and market analyses and a survey of 675 farmers in 9 European countries, difficulties and conditions for success have been identified. The most salient features and future outlook are presented in terms of scientific/technical aspects, production costs and return on investment as well as (somewhat unexpected) factors deemed to be most influential on the evolution of the biocontrol market in the coming decades.