In March 2018, RSK acquired Central Alliance, a pre-construction services company headquartered in Wakefield, UK. The company provides ground investigation, geo-construction, training, technology and survey services to the UK construction, defence, rail, utilities and transport sectors. Through its in-house experts and up-to-the-minute technology such as satellite imagery, aerial drones and muon tomography, Central Alliance has been helping high-profile clients, including Highways England and Network Rail, to deliver major infrastructure projects. With the addition of Central Alliance, RSK has more than 100 drilling rigs with an equal number of trained crews, in-house laboratories and greater site investigation capability than its rivals.