The use of on-premises technology in the business environment to create a competitive advantage is ushering in a new era known as digital transformation. Although companies are aware of its potential benefits, they face challenges creating a clear roadmap to reform their existing processes in line with these technologies. Maturity models are developed to assist organisations by providing extensive guidance and a roadmap for improvement. However, as a result of the systematic literature review and its analysis, it was observed that none of the 18 existing maturity models in the digital transformation domain fully satisfies all the criteria of suitability, completeness, clearness, and objectivity. To close this research gap, this study aims to develop a holistic maturity model in the digital transformation domain, entitled DX-CMM, by applying a theoretically grounded development approach, which has so far been neglected despite its remarkable relevance. The purpose of DX-CMM is to assist organisations by providing current capability and maturity determination, deriving a gap analysis, and creating a comprehensive roadmap for improvement in a standardised way. An exploratory case study is also conducted to check the applicability of the model in this study.