Purpose The paper aims to review the literature on Six Sigma projects through a broad framework of Six Sigma project selection process. It proposes a process framework approach of six sigma project selection and enumerates various recent tools and methods required for each stage. The review aims to expand the domain of Six Sigma project selection by identifying the importance of project portfolio approach. Design/methodology/approach The study used a process framework approach and systematic literature review to identify and classify various literature pertaining six sigma projects and its associated tools and methods Findings The paper provides broad insights about the opportunity and direction to future research in the area of Six Sigma project. Emerging research opportunities exist in the area of Six Sigma project risk management and selecting portfolio of projects. Research limitations/implications The study has its own limitations because of its chosen research approach. The process framework developed for classification of literature is based on expert opinion. Further research can be carried out to validate it. Practical implications This study will benefit new researchers entering the field of Six Sigma to identify new research opportunities and issues for their research interest. Second, industry practitioners and consultants working in the area of Six Sigma may work towards more successful implementation of Six Sigma. Originality/value The paper fulfils an identified gap of review of Six Sigma project selection.