Building and space ventilation rates are primary determinants of indoor pollutant levels and occupant exposures, and the impacts of ventilation on health and comfort have long been recognized in ventilation standards and regulations. Despite the importance of ventilation, its measurement is often neglected in indoor air quality studies. In cases when ventilation rates are presented, the measurement approaches are often not described in sufficient detail to evaluate their quality or applicability to the study. Ventilation measurements in 26 indoor air quality studies are evaluated in terms of the method employed, the thoroughness with which they were described, the metrics reported, and how key factors were addressed. The results reveal the use of a number of different ventilation performance parameters and a generally poor description of the measurement methods. The paper also makes recommendations on the information that should be included when reporting building ventilation rate measurements.