Costain Group PLC is an engineering and construction company. The Company operates in four business segments: Environment, Infrastructure, Energy & Process and Land Development operations in Spain. It provides front-end engineering consultancy, construction and ongoing care and maintenance services across market sectors including water, waste, power, rail, hydrocarbons and chemicals, highways and nuclear process. Its Environment division consists of its operations in the water, waste, education and retail sectors. Infrastructure division includes its operations in the highways, rail and airports sectors.The Energy & Process division includes its operations in nuclear, power and hydrocarbons and chemicals sectors. Its land development division is responsible for the Alcaidesa land and marina development activity in Southern Spain. On August 20, 2011, the Company acquired Promanex Group Holdings Limited. On April 6, 2011, it acquired ClerkMaxwell Limited.