Many workers in the United States are at the mercy of unpredictable scheduling practices, often facilitated by new technologies where computer algorithms create employee schedules based on projected consumer demand. Unpredictable schedules can be found in many occupations but are most common in retail and service industries—the very industries in which workers also face a lack of benefits, poor working conditions, and insufficient pay. For many, unpredictable schedules are caused by “just-in-time” scheduling software, which seeks to match the correct number of workers with demand but wreaks havoc on workers who have no control over a schedule that changes from day-to-day, or even hour-to-hour. This issue brief examines the economic and legal context in which unpredictable scheduling became popular, and then looks at the consequences for individuals, firms, and the broader U.S. economy.