The history of the use of intelligence tests has been summarized as a series of overlapping waves of new ideas and practices. In Wave 1 (1904 to present), intelligence tests were primarily used to measure general intelligence. In Wave 2 (1940s to present), practitioners were encouraged to generate nuanced hypotheses about individuals based on highly specific aspects of test performance. In Wave 3 (1970s to present), greater psychometric rigor was applied to the interpretation of individual profiles. In Wave 4 (1980s to present), test publishers began to operationalize well-developed theories of cognitive ability, giving practitioners greater confidence in their interpretations. We review how thoughtfully applying ideas and techniques from each approach can enhance current practice.