Penny Wise and Effect Size Foolish

—Although much developmental research is focused on basic science, some applied studies aspire to concrete policy recommendations. We suggest several steps that these studies might take to increase their chances of success. Scaling policy‐relevant variables in useful ways is a simple example. Most important is providing even rough estimates of the costs and benefits of recommended policy changes. Cost–benefit calculations are particularly useful because they indicate whether a policy or a program is likely to be an effective investment of public funds.