Robert Samuel Langer is an American biotechnologist, engineer, scientist, entrepreneur, inventor and the David H. Koch Institute Professor at the Massachusetts Institute of Technology. He was born on August 29, 1948 in Albany, New York, United States. Robert S. Langer completed his undergraduate stidies in Chemical Engineering at Cornell University and obtained his Sc.D in Chemical Engineering at MIT.  He joined MIT as Assistant Professor of Nutritional Biochemistry in 1978. Langer worked with Judah Folkman at Boston Children's Hospital to isolate the first angiogenesis inhibitor, a macromolecule to block the spread of blood vessels in tumours. Macromolecules tend to be broken down by digestion and blocked by body tissues if they are injected or inhaled, so finding a delivery system for them is difficult. Langer's idea was to encapsulate the angiogenesis inhibitor in a noninflammatory synthetic polymer wafer that could be implanted in the tumor and control the release of the inhibitor. He eventually invented polymer systems that would work. This discovery is considered to lay the foundation for much of today's drug delivery technology. He also worked with Henry Brem of the Johns Hopkins University Medical School on a drug-delivery system for the treatment of brain cancer, to deliver chemotherapy directly to a tumor site. The wafers or chips that he and his teams have designed have become increasingly more sophisticated, and can now deliver multiple drugs, and respond to stimuli.

He has received numerous other awards, including the Gairdner Foundation International Award (1996), the Lemelson-MIT Prize for invention and innovation (1998), the Othmer Gold Medal (2002), the 10th Annual Heinz Award in the category of Technology, the Economy and Employment (2003), the Harvey Prize in Science & Technology and Human Health (2003), the Dan David Prize (2005) and the Albany Medical Center Prize in Medicine and Biomedical Research (2005).