A data centre comprising a plurality of sections assembled together to define a unitary structure such that there exists at least one personnel area that spans at least two sections , the sections comprising a first section and a second section, the first and second sections each including a ceiling portion and a plurality of vertical support members supporting the ceiling portion , wherein the data centre accommodates multiple networked computer servers in IT racks arranged in rows and defining therebetween a plurality of hot aisles interleaved with a plurality of cold aisles, and utilises an above floor cooling regime in which cooling air is provided to the cold aisles and hence to the computer servers via a personnel corridor; wherein components of different services are mounted on the ceiling portions of the first and second sections , services of the first section being connected by means of a junction to corresponding services on the second section , the services including (i) services providing electrical power and powering servers in the IT racks, and (ii) services providing data transfer to and/or from such servers; the components including at least one of a busbar, a cable tray, a light fitting, a length of network cable, and a fire suppressant conduit; and, trunk-like services in the first and second sections are supported by the ceiling portions, whereby the ceiling portions provide the only supporting structure for provision of the trunk-like services to the IT racks; characterized in that the sections are each assembled from kits of parts, the kits of parts having a first transport configuration, and a second assembled configuration in which the kits of parts form the sections , wherein the sum volume of the kits of parts in the first transport configuration is smaller than the sum volume of the kits of parts in the second assembled configuration. wherein the data centre accommodates multiple networked computer servers in IT racks arranged in rows and defining therebetween a plurality of hot aisles interleaved with a plurality of cold aisles, and utilises an above floor cooling regime in which cooling air is provided to the cold aisles and hence to the computer servers via a personnel corridor; wherein components of different services are mounted on the ceiling portions of the first and second sections , services of the first section being connected by means of a junction to corresponding services on the second section , the services including (i) services providing electrical power and powering servers in the IT racks, and (ii) services providing data transfer to and/or from such servers; the components including at least one of a busbar, a cable tray, a light fitting, a length of network cable, and a fire suppressant conduit; and, trunk-like services in the first and second sections are supported by the ceiling portions, whereby the ceiling portions provide the only supporting structure for provision of the trunk-like services to the IT racks; characterized in that the sections are each assembled from kits of parts, the kits of parts having a first transport configuration, and a second assembled configuration in which the kits of parts form the sections , wherein the sum volume of the kits of parts in the first transport configuration is smaller than the sum volume of the kits of parts in the second assembled configuration. <EOS>