Background: Emerging research shows that the composition of movement behaviors throughout the day (physical activities, sedentary behaviors, sleep) is related to indicators of health, suggesting previous research that isolated single movement behaviors maybe incomplete, misleading, and/or unnecessarily constrained. Methods: This brief report summarizes evidence to support a 24-hour movement behavior paradigm and efforts to date by a variety of jurisdictions to consult, develop, release, promote, and study 24-hour movement guidelines. It also introduces and summarizes the accompanying series of articles related specifically to 24-hour movement guidelines for the early years. Results: Using robust and transparent processes, Canada, Australia, New Zealand, South Africa, and the World Health Organization have developed and released 24-hour movement guidelines for the early years: an integration of physical activity, sedentary behavior, and sleep. Other countries are exploring a similar approach and related research is expanding rapidly. Articles related to guideline development in South Africa, the United Kingdom, Australia, and by the World Health Organization are a part of this special series. Conclusions: A new paradigm employing 24-hour movement guidelines for the early years that combines recommendations for movement behaviors across the whole day is gaining momentum across the globe.