<p>Scholars in psychology increasingly apply a behavioral ecology/adaptive calibration framework to understand how childhood harshness and unpredictability shape downstream psychology, physiology, and behavior. Adapted from evolutionary biology, behavioral ecology in psychology has conceptualized harshness as morbidity/mortality and unpredictability as fluctuations in morbidity/mortality within an environment. Broad theoretical conclusions about adaptive calibration based on the body of work in psychology are limited by the fact that these factors have been conceptualized and operationalized in so many different ways that comparisons within harshness or unpredictability, and according to both original theory and theory specific to psychology, are difficult. As a starting point, we conducted a systematic (PRISMA) review of the psychology behavioral ecology literature in order to classify and assess the frequency of use of extant conceptualizations and operationalizations of childhood harshness and unpredictability (final papers <i>N</i> = 156; measures of harshness <i>N</i> = 199; measures of unpredictability <i>N</i> = 78), describe the attributes of designs and samples of these studies, and create a database with all of these measures. We then consider heuristic strengths and weaknesses of various kinds of measures, make suggestions for best practices, and discuss theoretical implications.</p>