Tetra Tech, Inc. is a provider of consulting and engineering services that focuses on water, environment, sustainable infrastructure, renewable energy, and international development. Its segments include Government Services Group (GSG) and Commercial/International Services Group (CIG). Its GSG segment provides consulting and engineering services to United States (U.S.) government clients (federal, state, and local) and development agencies. GSG supports U.S. government, civilian and defense agencies with services in water, environment, sustainable infrastructure, information technology, and disaster management. It provides engineering design services for U.S. municipal and commercial clients, in water infrastructure, solid waste, and infrastructure designs. Its CIG segment provides consulting and engineering services to U.S. commercial clients, and international clients that include both commercial and government sectors. CIG supports commercial clients across the Fortune 500.