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An academic journal’s impact factor (hereafter, JIF) is an average measure of the frequency with which articles within that journal are cited. For any given year, JIF is defined as the ratio of the number of citations to articles published in the pre-vious 2 years in that journal, to the total number of articles published in the journal over that same 2-year period. JIFs were originally developed to allow different journals to be ranked by relative impact within a discipline (Garfield, 1972). Individual scientists can readily access JIFs through the ISI Web of Science to assess both the merit of colleagues ’ work and the likely impact of publishing their own work in a par-ticular journal. Institutional policy makers can also use such information when evaluating individuals for academic appointments and promotions. Some national and institutional policies that allocate resources to individuals and to depart