Companies need to develop more sustainable management models to support a strategy focused on the environment and society, preventing the sole ambition to maximize economic profits. Several specific tools and frameworks have been developed for the implementation of sustainability management. However, the isolated adoption of new management practices could increase bureaucracy and constrain the development of an effective and systematic sustainability strategy. Based on the development of four case studies of relevant companies based in Portugal, this research presents a cyclical process with the structures, inputs and outputs, and roles in embodying sustainability in Integrated Management Systems (IMS). The originality of the work lies in the level of integration. Beyond identifying interconnection areas, it also specifies the Management Systems Standards (MSS) requirements in each area, assigning different roles in the integration process: drivers, efficient enablers, pathways, and evaluators. These four roles promote the claimed integration in a systematic cyclical process, plan–do–check–act (PDCA), to assist the consolidation of sustainability management. This research reinforces the added value of the IMS. It expands its scope, helping companies implement sustainability effectively and systematically, resulting in the presentation of Conceptual Sustainable Management Systems Standards (SMSS).