This paper addresses if calf health does affect feedlot performance and carcass value. The physiological aspects of this question as well as a regression analysis to further evaluate this problem will be addressed in this paper. A large set of data that can help to explain this health and value question has been made available for this study. These data were collected from the years 1990 - 2005 from a cattle feeding and carcass program in Coyle, Oklahoma as part of an Oklahoma State University program entitled the OK Steer Feedout (University 2004-2005). The information found in the physiological examination of this question indicates that calf health greatly affects feedlot performance and carcass value. The loss of muscle and fat deposits due to the immune response launched by the calf to fight disease, suggests a loss in marbling and carcass weight. The decrease in appetite creates a lower average daily gain, affecting the out weight of the calf. The symptoms seen as a result of infection affect feedlot performance, yield grade, and quality grade. The extent of the influence of sickness on the characteristics that determine performance characteristics was determined by the regression models. The models indicate medical costs (which indicate sick cattle) negatively affect performance characteristics. To cow/calf producers, this creates the opportunity to provide healthy cattle and to be justified in receiving a premium for their product. For feedlots and stockers, it means a more valuable consistent product, cattle with better average daily gains, and fewer days on feed. Economically, the cattle industry stands to benefit from the promotion of healthy cattle. How much they stand to benefit requires further research.