R ehabilitation is the health strategy of the 21st century. 1,2 In retrospect, the 19th century was the century of prevention, resulting in an almost doubling of life expectancy by improving the availability of clean water, sewage, sanitation, vaccination, and nutrition and making these services available to the entire population in developed countries. The 20th century added additional years of life with emergency services and surgery leading to increased survival of previously lethal injuries, pharmacological treatments including antibiotics, immune suppressants, and cancer treatments that turned previously major infectious conditions such as HIV and a range of cancers into chronic diseases. The challenge of the 21st century is now to optimize functioning in people with acute and chronic conditions and aging-"adding life to years."According to the World Health Organization's (WHO) global estimates of the need for rehabilitation based on the global burden of diseases study of 2019, 3 2.41 billion individuals live with