Quality directly influences organizational performance in the manufacturing industry. Through an examination of literature, critical success factors that lead to the implementation of six-sigma in the manufacturing industry are identified for organisations of differing sizes: SMEs, large enterprises and general/unspecified organisations (not specified as either SMEs or Large in literature). It is found that general success factors across organisations (unspecified) include Employee Education/Training, Top Management Commitment, Project Selection, Employee Involvement/Communication, Project Management/Leadership. While for large enterprises the following factors were identified: Project Selection, Alignment with Customer Requirements, Employee Education/Training, Senior Management Commitment, Use of Quality Tools, Visible Cost Saving. The results serve as a guide for a better understanding of the requirements leading to the successful implementation of six-sigma in organizations and where to best direct resources.