The need to optimize rather than maximize rates of reproduction has been demonstrated for various production situations. In a highly intensive system, incorporating the use of artificial insemination, increasing the calving rate from 75 to 85% did not yield more saleable beef. Under ranching conditions, gross margins increased parallel with calving rate, but the margin per cow did not always follow this trend. In Sourveld areas it will probably not be profitable to improve calving rates by additional short-term feeding during winter. The negative effect –on reproduction rate of over-emphasis on growth rate to weaning has been reviewed and the efficiency of various genotypes was evaluated for different environments.