Information is provided on total costs, cost elements, and other related background aspects of validation research. Cost elements covered were staff time (broken into researcher and clerical, subject matter expert, and research participant), overhead, travel, and miscellaneous costs. Information is reported for 21 studies or groups of studies. In round figures, costs ranged from $24,000 to $673,000 for criterion-related studies and from $8,000 to $1,245,000 for content validity studies. Information was gathered by telephone or personal contact with principal researchers or other persons having a detailed knowledge of recent validation studies. Because many persons were reluctant to mention individually identifiable cost figures, all studies are described in general terms and the accuracy of the information is unknown. (Author/RL)