In 2021, the global mergers & acquisitions (M&A) market remained strong, with transaction volumes reaching $5.9 trillion and an increasing number of large deals. Despite the strategic impact and the high priority of every transaction, many of them fail to deliver the anticipated value due to inferior implementation, both from a post-merger IT integration (IT PMI) and an IT carve-out perspective. This paper explains how one of the world’s largest engineering companies (TURBO) has developed IT M&A capabilities to ensure both efficient post-merger IT-PMI and IT-carve-out projects. Their key to success relies on two principles, (1) standardization of the IT integration and respectively IT separation (carve-out) process, and (2) standardization of the enterprise architecture. By establishing these principles, TURBO managed to reduce both time and costs of its IT integration and IT carve-out projects by on average 40 %. Based on this case study, the paper synthesizes four success factors that can inform managers of M&A active organizations to successfully build IT-PMI and IT-carve-out capabilities.