Resumen
In order to provide a common ground for the Special Issue ?Water quality and agricultural diffuse pollution in light of the EU Water Framework Directive,? this review sets out to provide a concise overview of the academic literature on two topics. First, we review the issues in the governance literature on the ?wicked problem? of diffuse agricultural sources focussing on three principles: (1) fragmentation and the distribution of power to address diffuse sources, (2) the problem of source-oriented and effect-oriented measures, and (3) contested knowledge for policies for diffuse sources. Second, we briefly sketch the literature on policy instruments and confront that with the scholarly understanding of addressing diffuse agricultural sources under the Water Framework Directive (WFD).