Profitable UK dairy farmers achieve competitiveness through efficiency gains thus meeting the challenge of producing quality food, meeting the needs of the market while minimizing their impact on resources and the environment. The best measure of economic efficiency at the farm level is net margin per litre of milk produced. This measure captures the effect of both technical, cost and scale efficiency and is therefore an attractive high level benchmark to use across production systems. The latest information from DairyCo’s MilkBench+ data base is that the variation in this measure of efficiency is large, with a difference of 12 ppl between the 25% highest net margin producers and the 25% lowest margin producers. This constitutes a significant opportunity for a large number of farmers to increase profits, production and sustainability. This project will develop an internet based service for dairy farmers and their approved advisors to manage dairy farm performance. The service will consist of three elements: (1) a sophisticated farm management tool on which users will record a structured set of data to be stored online. This unique system will allow point of use data capture of all physical and financial inputs to the business. (2) the programme will provide analysis for weekly, monthly and annual performance reviews in real time (3) the web service will also provide an analytical tool for users to carry out their own analysis. This part of the service is aimed at advisers. The project requires significant development and will provide a step change in the way farmers and advisors are able to use data on farm. The management tool that this project will develop aims to equip 21st century farmers to meet the challenges of the next decade, satisfying an increasing world demand for food while minimising the impact of production on natural resources