FDMS (which stands for Farmland Diversity Management Simulator) is an original software able to simulate the effect of farmland diversity and forage management practices on land use during a growing season in dairy farming systems. In this paper we describe how students, scientists or advisors can use this software to test different environmental scenarios (weather data and field characteristics) and management strategies at the farm scale. © 2007 Elsevier B.V. All rights reserved.