Green supplier development program selection using NGT and VIKOR under fuzzy environment

•We investigate the problem of green supplier development program evaluation.•The approach can be applied under limited or no quantitative data.•Program evaluation uses linguistic ratings (fuzzy numbers) obtained from experts.•An integrated approach based on NGT and fuzzy VIKOR is proposed.•Sensitivity analysis is performed. Developing environmental performance of suppliers is critical for green supply chain management. Organizations are nowadays investing in various green supplier development programs to enhance their supplier performances. The decision to select the right program for green supplier development is often a challenging decision due to lack of prior experience, limited quantitative information, specific context of the organization, and varying supplier backgrounds. This paper addresses the problem of evaluating green supplier development programs and proposes a fuzzy NGT (Nominal Group Technique)-VIKOR (VlseKriterijumska Optimizacija I Kompromisno Resenje) based solution approach. NGT is used to identify criteria for evaluating green supplier development programs. Fuzzy theory is used to address qualitative (linguistic) ratings for the alternatives and the selected criteria used under lack of quantitative information. VIKOR is used to generate green supplier development program rankings and recommend the best program(s) for implementation. Sensitivity analysis is performed to determine the influence of modeling parameters on ranking results of alternatives. A numerical application is provided.