Technical Abstract: Phosphorus originating from agriculture has long been recognized as an important source of P in surface waters. Successful implementation of management practices to reduce nonpoint P pollution must address not only the technical aspects of P transport, but also the economic, social, and political considerations that affect farmers' willingness to adopt and maintain these practices. This paper provides an overview of best management practices (BMPs) for controlling point and non point source P pollution from agriculture. Practices are organized by the scale at which they are applied (farm, field, and watershed/region), as well as by the mechanism of P transfer (source vs. transport) that they address. Issues affecting implementation of BMPs are reviewed. Finally, two U.S. case studies are presented to illustrate innovative efforts to address non-point source P pollution from livestock and field crop agriculture.