Environmental targets for dairy farming are necessary to help ensure that milk is produced in a sustainable way. However, setting such targets is not an easy task due to the variety of both dairy farming systems and methods for assessing environmental impacts. The IDF and FAO have undertaken important work, attempting to harmonize the methods for environmental assessments of the dairy sector and reduce confusion in published results. This chapter reviews the main, internationally accepted methods available to evaluate the environmental impact of dairy farming, identify levers of action and set environmental targets. It also highlights what further work is needed on water footprints and dairy ecosystem services in order to ensure a holistic approach to the environmental performance of dairy farms.