Appropriate technology is a movement (and its manifestations) encompassing technological choice and application that is small-scale, affordable by locals, decentralized, labor-intensive, energy-efficient, environmentally sustainable, and locally autonomous. It was originally articulated as intermediate technology by the economist Ernst Friedrich "Fritz" Schumacher in his work Small Is Beautiful. Both Schumacher and many modern-day proponents of appropriate technology also emphasize the technology as people-centered.

Appropriate technology has been used to address issues in a wide range of fields. Well-known examples of appropriate technology applications include: bike- and hand-powered water pumps (and other self-powered equipment), the bicycle, the universal nut sheller, self-contained solar lamps and streetlights, and passive solar building designs. Today appropriate technology is often developed using open source principles, which have led to open-source appropriate technology (OSAT) and thus many of the plans of the technology can be freely found on the Internet. OSAT has been proposed as a new model of enabling innovation for sustainable development.

Appropriate technology is most commonly discussed in its relationship to economic development and as an alternative to technology transfer of more capital-intensive technology from industrialized nations to developing countries. However, appropriate technology movements can be found in both developing and developed countries. In developed countries, the appropriate technology movement grew out of the energy crisis of the 1970s and focuses mainly on environmental and sustainability issues. Today the idea is multifaceted; in some contexts, appropriate technology can be described as the simplest level of technology that can achieve the intended purpose, whereas in others, it can refer to engineering that takes adequate consideration of social and environmental ramifications. The facets are connected through robustness and sustainable living.