Data centresare complex eco-systems that interconnect elements of the ICT, electrical, and mechanical fields of engineering and hence the efficient operation of a data centre requires a diverse range of knowledge and skills from each of these fields. The Innovation Value Institute (IVI), a consortium of leading organizations from industry, the notforprofit sector, and academia, have developed a maturity model that offers a comprehensive,value-based method for organizing, evaluating, planning, and improving the energy efficiency of mature data centres. The development process for the maturity model is discussed, detailing the role of design science in its definition.