Computer adaptive testing systems are feasible for certification and licensure testing. This is in part due to the availability of extensive yet inexpensive computers. Modern item response theory, combined with computerized adaptive testing, yields a powerful new method of testing which provides greater accuracy and efficiency and less boredom for the examinee. The computer presents each item, scores it, and then selects the next item which is appropriate for the individual examinee; thus, individual testing is much more feasible than it would be using human examiners. There are additional advantages: acceptable accuracy can be achieved with fewer items; more accurate estimates can be obtained at the extreme ends of the ability continuum; test security is improved; tests can be administered on demand when needed; and a greater variety of item types may be included. With licensing and certification tests, it is important to obtain a good pool of test items, to be accurate near the minimum cutting score, to have appropriate unidimensionality, and to use computers in a comfortable environment. It is also useful to have a large number of examinees, approximately 1000 or more. Cost estimates are encouraging, especially when the computer systems are used often. (GDC)