A series of four vocabulary norming tests was used to develop a large, homogeneous pool of vocabulary test items for use in computer-administered adaptive testing research. Five hundred seventy-five unique vocabulary knowledge items were divided among the four norming tests, and administered to separate groups of college undergraduates. Norming tests were administered by computer or paper and pencil in fixed and random order. Analyses showed no effects due to item order or mode of administration. Item difficulty and discrimination indices of both the classical test model and the normal ogive item model were derived on the norming data. On the basis of item analysis results, 369 items were selected as satisfactory for the adaptive testing item pool. Factor-analytic studies of subsets of the 369 items confirmed the assumption of unidimensionality of the selected item pool. On the basis of known technical limitations in the research and the unique problems of developing item pools for adaptive testing, an outline was developed for the design of future norming studies specifically intended to develop large homogeneous pools of test items for use in computer-administered adaptive ability measurement. (Author)