Purpose: The purpose of this research is twofold; firstly, to propose and test a measuring instrument for the efficient and effective integration of management systems (MSs), identifying the particular aspects that may distinguish the substantive (internalized) from the superficial (ceremonial) integration; and secondly, to propose and test a scale for corporate sustainability performance (CSP). Design/methodology/approach: A literature review has identified pertinent variables and yielded relevant measuring items. A field survey has been conducted. The survey instrument has been administered to Greek organizations certified to two or more MS standards. Collected data from 280 respondents has been processed using exploratory factor analysis. Findings: Internalization has been identified as the main construct to interpret substantial MS integration in terms of resources and the extent of integration. The extracted internalization factors are human resources, strategic resources, information systems, integration tools, outsourcing, internal processes integration level and audits' integration level. CSP has been operationalized in terms of the company's relationships with its stakeholders. The extracted CSP factors are customer–supplier relationship, the employees, investors/shareholders, financial institutions, the environment, state and society. Practical implications: This research findings can be used by management professionals, certification bodies and governmental authorities in order to foster the implementation of multiple MSs and highlight the critical issues for their successful integration and internalization, which is imperative for their prosperity and contribution toward CSP. Practitioners are also provided with an instrument to monitor CSP through the company's relationships with its stakeholders toward satisfaction of their needs. Originality/value: To the best of the authors' knowledge, this is the first empirical study on the internalization of integrated MSs. In addition, the development of a CSP scale intends to bring together corporate sustainability management with CSP. © 2020, Emerald Publishing Limited.
