How do core business and manufacturing capabilities enable strategies for sustainable manufacturing, and what are those capabilities? This paper proposes a Capability Methodology for Sustainable Manufacturing (CMSM) for allowing top management of manufacturing companies to address these questions. A diagnostic tool was developed from three case studies based on a set of interview questions aimed at identifying core capabilities and sustainability issues in manufacturing companies. Interview data was coded and mapped through a relational matrix formulation that describes four archetypes for the development of sustainability strategies. The matrix maps the degree of complexity of the sustainability concept as understood by the company, and the scope of the product life cycle being considered. It is argued that the methodology helps bring awareness to managers of any gaps or mismatches between their actual core capabilities and the desired outcomes for sustainable manufacturing.