Lean Six Sigma (LSS) initiatives often yield impressive results in the short term, such as cost reductions, cycle time improvements, and enhanced customer satisfaction. However, the real challenge lies in sustaining these gains over the long term. Without a structured approach to embedding LSS principles into organizational culture, the initial successes can quickly erode, leaving teams frustrated and stakeholders disillusioned. This article explores best practices for ensuring that Lean Six Sigma gains endure and continue delivering value to the organization.