In this doctoral thesis data of modern draught horse technology has been collected scientifically, using mowing as an example. Field research with seven different horse drawn and two tractor drawn alternatives has been conducted, examining different parameters regarding requirements and performance of the tested alternatives. The results encompassing amongst others draught load, risk of soil compaction, energetic efficiency, emissions, physiological parameters of the horses show the horses to be superior to tractors in any case but speed, output and methane production. The character of the horses and the skilfulness of the driver have great influence on the results. Liability to the soil is less in horse work than in tractor work and the topsoil is less compacted by horse work while the subsoil is not compacted at all. Maximum area that can be worked with horses per day is limited by the needs of feeding and regeneration of the horses.The double-knife mower with 1.90 m working width hitched to a fore cart equipped with an engine-driven power-take-off is assessed to be the most advisable of the examined horse drawn alternatives.