During the past centuries, various techniques have been described to prevent patients from assuming the supine position such as an upright sleep posture, positional alarms, verbal instructions, tennis balls, vests, “shark fins” or special pillows. Different inventions have been patented over the years. Scientific research shows that positional therapy has a significant influence on the apnoea–hypopnoea index. These studies are predominantly performed as case series on a comparably small number of patients. The aim of this chapter is to provide an overview of the literature on positional therapy and its origin and evolution. A broad search strategy was run electronically in the MEDLINE, Embase and Google Scholar databases using synonyms for position, sleep apnoea, positional therapy and patents. Next to a great number of patents, 17 scientific studies were found which examined the effect of positional therapy on OSA. In this chapter we discuss the various techniques, results and compliance rates. Long-term compliance for positional therapy remains an issue, and although remarkable results have been shown using innovative treatment concepts for positional therapy, there is room for both technical improvement of the devices and for further long-term research.