Tetra Tech, Inc. operates as a global provider of specialized consulting and engineering services. The firm organizes its activities into two primary divisions: the Government Services Group (GSG) and the Commercial/International Services Group (CIG). The GSG division delivers a comprehensive suite of solutions, encompassing initial data collection and ongoing monitoring, advanced data analytics and information management, practical scientific and engineering research, intricate engineering design, thorough project management, and continuous operations and maintenance support. Furthermore, it offers expert consulting on climate change and energy efficiency, alongside services dedicated to the evaluation, certification, reduction, and overall management of greenhouse gas emissions. This segment primarily supports federal, state, and local governmental bodies, as well as various development agencies. Its areas of expertise include water resource analysis and management, environmental surveillance, data intelligence, public sector advisory, waste disposal solutions, and broad civil infrastructure master planning and engineering initiatives. Conversely, the CIG division provides a similar array of essential services, including early data acquisition and surveillance, data interpretation and information governance, viability studies and assessments, applied science and engineering investigations, engineering scheme development, project execution oversight, and operational sustainment. This segment's clientele spans the natural resources, energy, and utilities industries, in addition to markets focused on sustainable infrastructure master planning and engineering design. Established in 1966, Tetra Tech, Inc. maintains its corporate headquarters in Pasadena, California.