The model for educational measurement developed by George Rasch, a Danish psychometrician, is reviewed and its application to occupational educational testing discussed. The Rasch model is an adaptation from the theory of latent trait analysis. According to it, answering an item correctly is a function of the difficulty of the item and the ability of the person being tested. The raw scores serve as the basis for estimating the scale of ability. The author concludes that the properties of the Rasch analysis suggest solutions to a number of measurement problems in occupational engineering including developing and equating alternate forms of a test and estimating and interpreting changes in trainee performance. The item-free characteristics of this measurement model may allow the development of individually tailored tests. (DJ)