People fail to follow through on all types of important intentions, including staying fit, studying sufficiently, and voting. These failures cost individuals and society by escalating medical costs, shrinking lifetime earnings, and reducing citizen involvement in government. Evidence is mounting, however, that prompting people to make concrete and specific plans makes people more likely to act on their good intentions. Planning prompts seem to work because scheduling tasks makes people more likely to carry them out. They also help people recall in the right circumstances and in the right moment that they need to carry out a task. Prompts to make plans are simple, inexpensive, and powerful interventions that help people do what they intend to get done. They also avoid telling people what to do, allowing people to maintain autonomy over their own decisions.