The effects of the medium of test administration—paper and pencil versus computerized—were examined for timed power and speeded tests of cognitive abilities for populations or young adults and adults. Meta-analytic techniques were used to estimate the cross-mode correlation after correcting for measurement error. A total of 159 correlations was meta-analyzed: 123 from timed power tests and 36 from speeded tests. The corrected cross-mode correlation was found to be. 91 when all correlations were analyzed simultaneously. Speededness was found to moderate the effects of administration mode in that the cross-mode correlation was estimated to be. 97 for timed power tests but only. 72 for speeded tests. No difference in equivalence was observed between adaptively and conventionally administered computerized tests. Some limitations on the generality of these results are discussed, and directions for future research are outlined.