Tetra Tech, Inc. is a provider of consulting and engineering services that focuses on water, environment, sustainable infrastructure, renewable energy, and international development. The Company operates through two segments: Government Services Group (GSG), and Commercial/International Services Group (CIG). GSG provides consulting and engineering services primarily to U.S. government clients (federal, state and local) and development agencies worldwide. GSG supports the United States government civilian and defense agencies with services in water, environment, sustainable infrastructure, information technology, and disaster management. CIG primarily provides consulting and engineering services to the United States commercial clients, and international clients that include both commercial and government sectors. CIG supports commercial clients across the Fortune 500, renewable energy, industrial, manufacturing, and aerospace markets.