The Institute for Environmental Science and Engineering (IESE) is an inter-disciplinary Organized Research Unit of the University of California at Berkeley. Created in 1950, in response to a state legislature mandate for research on water pollution and solid waste management, the ORU was initially called the Sanitary Engineering Research Laboratory. The name was changed in 1982 to the Sanitary Engineering & Environmental Health Research Laboratory. In 1992 the Regents of the University of California approved the name change to the Environmental Engineering & Health Sciences Laboratory. As part of a reorganization of the ORU during a University-wide review in 2000 the name changed to the Institute for Environmental Science and Engineering.

In many respects, ISES serves as a bridge between basic research, often associated with an academic environment, and the more applied studies necessary for sound environmental management. IESE is thus very different from the typical university research unit, and equally distinct from industry, which is actually involved in design and construction. In this unique position, IESE is able to focus the expertise available throughout the University of California on environmental problems of current and future concern.

By the 1994-1995 year, research programs in the Laboratory were in three general areas: water and wastewater treatment; pollutant effects in lake and estuarine ecosystems; and environmental and occupational health. During 1995-1996 IESE was part of a campus-wide review of all Organized Research Units. As a consequence of the review, IESE's budget was reduced by 50% as of July 1, 1996 which eliminated 1.5 staff research positions. Several additional faculty joined IESE and supported research continued to expand to include geomorphology and chemical exposure. On July 1, 1996, along with support for research and educational facilities it always provided, IESE began providing research management services. The number of affiliated faculty greatly expanded and IESE's focus was broadened in 1996-1997 to include environmental pathogens, applied ecology, air quality, water re-use, mineral exploration, bioengineering and nuclear waste management. IESE expanded its research management services at the beginning of the 1997-1998 fiscal year to include proposal preparation.