Robert S. Langer, American chemical engineer, entrepreneur, and academic
Robert Samuel Langer, Jr. FREng (born August 29, 1948) is an American chemical engineer, scientist, entrepreneur, inventor and one of the twelve Institute Professors at the Massachusetts Institute of Technology.He was formerly the Germeshausen Professor of Chemical and Biomedical Engineering and maintains activity in the Department of Chemical Engineering and the Department of Biological Engineering at MIT. He is also a faculty member of the Harvard–MIT Program in Health Sciences and Technology and the Koch Institute for Integrative Cancer Research.

Langer holds over 1,400 granted or pending patents. He is one of the world's most highly cited researchers and his h-index is now 299 with currently over 363,000 citations. He is a widely recognized and cited researcher in biotechnology, especially in the fields of drug delivery systems and tissue engineering.He is the most cited engineer in history and 4th most cited individual in any field, having authored over 1,500 scientific papers, and is also a prolific entrepreneur, having participated in the founding of over 40 biotechnology companies including Moderna.

Langer's research laboratory at MIT is the largest biomedical engineering lab in the world; maintaining over $10 million in annual grants and over 100 researchers. He has been awarded numerous leading prizes in recognition of his work.