Improvement of the economic position of the farm or ranch is an ongoing process for many commercial cow-calf producers. Profitability may be enhanced by increasing the volume of production (i.e. the pounds of calves you market) and/or the value of products you sell (improving quality). The reduction of production costs, and thus breakeven prices, can also improve profitability. For commercial beef producers, the implementation of technologies and breeding systems that increase the quality and volume of production and/or reduce input costs is essential to maintain or improve the competitive position of the operation. Profitability is influenced by these factors concurrently. Efficiency is the proportion of outputs to inputs and is frequently used by beef producers. There are many different ‘efficiencies’ that affect beef production, especially at the cow-calf level. Some of these efficiencies are observed at the individual animal level and some observed at the system or herd level. The various efficiencies can be categorized into with measures of biological or economic efficiency. Improvement in individual animal efficiency, especially during the post-weaning growing or finishing phases, may or may-not improve efficiency at the herd or system level, and may have undesirable correlated response in traits of cows.