New methods of design and analysis for mixed grazing experiments are proposed and compared with previously reported designs. In general, with previous designs the effects of mixed grazing per se were confounded with other factors. The concepts of equality of grazing pressure and of livestock equivalents are examined and criticized when used as starting points for mixed grazing experiments. Two year's results of a mixed grazing experiment with cattle and sheep are analysed and provide evidence that mixed grazing is beneficial to both species in terms of production per animal. A simple economic analysis shows how the price ratio between the value per unit weight gain of the two species can be used to decide on the area of financial benefit from mixed- as opposed to single-species enterprises.