The role of outsourcing in attaining competitive advantage and improving business performance has been widely discussed. Due to growing awareness of the importance of environmental and social responsibility issues, outsourcing firms see these issues as a strength that can be used to become more sustainable in the face of global competition. Therefore, based on an extensive literature review, a model consisting of six constructs (reducing operating costs, improving company focus, access to world- class capabilities, unavailability of internal resources, competitive capabilities, and business performance) was developed to discover ways to push outsourcing firms to support sustainability efforts. Utilising the first-order confirmatory factor analysis (CFA) approach, a final 29-item survey covering six measurement constructs was developed and verified. The convergent validity of the constructs was also validated. The results provided an adequate fit to the Malaysian manufacturing SME data. The findings also highlighted some theoretical and methodological issues in relation to the application of the validated constructs in future work.