Health-related quality of life (HRQL) outcomes evaluation is becoming an important component of clinical trials of new pharmaceuticals and medical devices. HRQL research provides patients, providers, and decision makers with important information on the impact of disease and treatment on physical, psychological, and social functioning and well-being. These outcomes are also useful to the pharmaceutical and device industries as they attempt to understand and communicate product value to physicians, patients, health insurers and others. HRQL labeling and promotional claims in the US are likely to increase over the next few years. The evidentiary requirements to make such a claim should be based on accepted scientific standards of HRQL evaluation and consistent with the regulatory requirements for clinical efficacy. This report outlines the scientific practices that should be considered in the evaluation of evidence for an HRQL claim, including the selection of appropriate domains, evidence to support the reliability and validity of HRQL measurement, considerations in research design and statistical analyses, and the issue of clinical significance. Representatives from the pharmaceutical and device industries, regulatory agencies, and the HRQL scientific community should work together to make certain the use of HRQL in labeling and promotion are based on sound scientific evidence, and that these messages are clearly and accurately reported to the consumers.