Milk production for the first 10 weeks was measured in Merino ewes grazed over a 3-year period on native and sown pastures at different stocking rates and under two systems of management; the growth of their lambs was also measured. It did not appear that milk production by the Merino ewe was a limiting factor In growth of single lambs. Lactation curves for the Australian Merino are different from those published for British breeds of sheep. Higher milk production was recorded in ewes: (a) rearing twin lambs as compared with single lambs; (b) rearing single crossbred lambs as compared with single Merino lambs.