The present study examines the separate and combined effects of environmental and organizational variables on hospitals' clinical IT sophistication in a multivariate framework. The analyses focused on two distinct but related questions. First, in the context of the bivariate hypotheses, what is the relative significance empirically of each of the environmental and organizational classes of variables? And second, within classes and on an overall basis, which specific variables make the largest contribution to explained variance in the dependent variable hospitals' clinical IT sophistication when all other variables are held constant? Data collected from 99 Texas hospitals are analyzed to assess the effects of the antecedent variables both within and across classes. Our findings suggest the bigger contribution of environmental antecedents to the level of clinical IT sophistication in hospitals, compared to that of organizational antecedents. We end by discussing the limitations and implications of the study.