None of the metabolic indicators which have been used to date provides a single or necessarily ideal endpoint for interventional management in wasting disorders. Some of these indicators may provide better endpoints for the acute rather than the chronic wasting conditions. In addition, it is imperative that more than one endpoint be selected to be assured that there is concordance in the findings. However, prior to the selection of any endpoint measure, the investigators involved must be fully cognizant of the potential pitfalls and errors that can occur in every one of the selected methodologies. In anticipating these potential problems, developing strategies for the interpretation of the data is critical at the outset of any interventional management strategy. The manufacturers, the regulators and the investigators involved in the interventional management of chronic and acute wasting disorders must agree on the endpoints to be used and these endpoints must provide the most appropriate and valid information. Selection of nutritional and metabolic endpoints must be in part dependent on the disease process involved, the potential magnitude of the interventional effect and must be utilized in the context of a carefully designed experimental protocol with a well focused question(s).