This article examines patterns of legal American immigration (migrations to the United States from abroad) and their direct impact on the acquisition of neuropsychological (NP) normative data for Hispanics. The nonrandom and selective nature of these migrations, and their accompanying demographic attributes, are shown to significantly influence the acquisition process. Specifically, the direct impact of several potential sources of bias while procuring NP norms is explored. Total number of immigrants (absolute immigration), occupational allegiance (and possibly education), and intended area of initial residence seem to play influential roles as a result of their direct impact on demographic characteristics known to have significant effects on neuropsychological performance. Possible solutions capable of enhancing the acquisition process are also addressed.