Kier Group plc operates in the infrastructure services, construction, and property development sectors, primarily in the UK. The company provides a range of services including civil engineering, building, and facilities management, focusing on delivering essential infrastructure projects. Kier generates revenue through contracts with public and private sector clients, serving markets such as transportation, water, and housing. Its operations are organized into segments that include construction, infrastructure services, and property development, emphasizing sustainable practices in its project execution.