AbstractStudies have been carried out to measure the response to selection for canopy characters, as measured on young spaced plants, and the associated changes in sward yield inLolium.In addition certain of the selection lines were compared with and found to be more productive than several existing bred varieties, indicating the considerable scope for improvement of dry matter yield through breeding.The canopy characters which were associated with high yield are compared with those which confer high yielding ability on a spaced plant and an individual in a community. The plant breeding implications of the results are briefly discussed.