Purpose - Thepurpose of this paper is to utilize critical success factors (CSF) andidentify items Green Belt (GB) practitioners note as barriers to completion of Six Sigma (SS) projects in a major manufacturer setting. Design/methodology/approach - The design of this paper is a descriptive study of a single location of a global manufacturer's internal data and survey of accredited GBs who have completed an SS project for company accreditation utilizing company focus on CSFs. Findings - The results demonstrate the GB practitioners have competing priorities, have time constraints and lack project management skills that reduce timely completion of SS projects. Top management responsibility for SS GB projects are defined through the CSFs of leadership, project management and project selection. Research limitations/implications - This study pertains to the single manufacturing location of a major, multinational company. The survey of SS GBs is limited to those individuals who have become accredited to company requirements, in the initial stages of strategic implementation, resulting in a small sample size. All GB projects follow the DMAIC (Define, Measure, Analyze, Improve and Control) methodology. The implications may be reproduced in similar environments where GBs conduct SS projects to test the robustness of the study. Practical implications - This study underscores the importance of proper coaching and mentoring of SS practitioners, especially thosewhoare expected to contribute asGBsin a part-time manner. Implementation of SS goes beyond initial deployment and requires active mentoring of GB practitioners to make sure that SS projects get proper focus. The results are relevant to both researchers and practitioners. Originality/value - This paper examines SS projects with a GB perspective, an important contribution to SS but lacking in the literature. While GBs are important to SS implementation, and serve as a pathway to fulltime SS personnel, there are few studies that note this work. This study will support practitioners in the importance of wider SS deployment through active support of GBs, where top management responsibility for GB success is defined through CSFs for improvement.