Purpose The purpose of this paper is to present the implementation of Lean Six Sigma (LSS) to reduce medication errors, by using four case examples. The paper will also suggest appropriate Lean and Sigma tools to improve the medication process. Design/methodology/approach The authors critically analyze four case examples that used LSS projects, to demonstrate the approach, benefits, success factors and lessons learnt. Findings LSS is a powerful process improvement methodology that could be applied by health-care sectors to reduce medication errors, increase patient safety and reduce operational costs. Common Lean and Six Sigma tools play a significant role in improving and sustaining the medication process. Practical implications It is necessary for the project team to select the most appropriate LSS tools to address medication process problems. Adoption of a LSS roadmap could help health-care organizations in the successful implementation of LSS. Originality/value The paper is valuable for health-care professionals seeking to reduce errors in the medication process or other processes that need to be improved.