With increasing Holsteinisation of the dairy herd, the milk production potential of dairy cows has increased substantially over the past two decades. This development presents new challenges for managing dairy cows during grazing, particularly where the objective is to maximise the proportion of energy in the diet derived from forage (Mayne and Peyraud, 1996). The objective of the current study was to explore forage supplementation strategies to maintain high milk yields from grass and forage in dairy cows during the grazing season. A second objective of the study was to examine the effect of concentrates of contrasting degradability on milk production.