Hem Gupta, founder of Environmental Systems Design (also known as ESD), died on February 10 at the age of 85.

The family did not disclose the cause of death.

A native of India, Gupta received his Masters degree in mechanical engineering from the University of Illinois. In 1954, he began his professional career at Skidmore Owings & Merrill. Gupta also worked for Epstein, and was Perkins + Will’s chief engineer when he launched his own firm, EDS, in 1967.