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Occasionally a psychologist may be faced with a puzzling MMPI-2 profile and need to make sense out of the sharp peaks and valleys etched on the paper in an unusual pattern never before seen. An examination of the available clinical scale cookbook resources provides little background information because the particular profile code turns out to be one of those that seems not to be well explored by the past MMPI researchers. What next? What information can the psychologist find to obtain an empirical perspective on this particular profile code? The interpreter can, of course, resort to generic scale descriptions in developing conclusions. However, clinical profile interpretation can be more effective and the conclusions drawn more specific to the case if relative frequency or base rate information is also available to put the profile into empirical context (Bathurst, Gottfried, & Gottfried, 1997). The base rate of a population was described by Finn & Kamphuis, (1995) as: What are your chances of being hit by lightning? Of winning a lottery? Of developing schizophrenia? The probabilities of these events, usually expressed in a percentage, are called base rates. Base rates are often calculated in clinica