Abstract: Data center assemblies include first and second arrays of information technology (IT) equipment cabinets defining a hot aisle. The data center assemblies also include an air containment assembly fluidly coupled to the hot aisle, at least one air-cooling unit fluidically coupled the air containment assembly, and/or at least one liquid-cooling system fluidically coupled to at least a portion of the IT equipment cabinets. The at least one fluid-cooling system includes a heat exchanger fluidically coupled to a cooling liquid loop and a fluid pump fluidly coupled to the heat exchanger and the at least a portion of the IT equipment cabinets. The air-cooling units and liquid-cooling systems may be designed to be interchangeable, allowing for seamless adaptation to changes in the number and types of IT equipment cabinets in a data center pod. The types of IT equipment cabinets may include air-cooled and liquid-cooled IT equipment cabinets.