Tetra Tech, Inc.
A consulting and engineering firm, Tetra Tech plans and builds water, environmental, and infrastructure projects worldwide — from flood control and water-quality systems to hazardous-waste cleanup and renewable energy. Four engineers founded it in Pasadena, California in 1966, and the Greek word "tetra" (four) honors both those four founders and their four original specialties: coastal engineering, research and development, geophysics, and systems analysis.