The research set out to interrogate the barrier and facilitators of Lean Six Sigma Implementation in Irish Pharmaceutical companies. To this end, the main objectives was to identify the factors that hindered and facilitated the successful implementation of; Lean Six Sigma in Irish pharmaceutical companies. To achieve its objectives, the qualitative method was adopted and data were sourced through primary and secondary methods with the research interview acting as a main source of data. A purposive sample of participants (n=5) were interviewed to get their perception of the barriers and facilitators to Lean Six Sigma in their organization, the participants were employees of five different pharmaceutical companies in Ireland. Thematic analysis was applied to interpret the data while comparing the results to that of similar studies. The study found out that the major factors that acted as barriers to the implementation of LSS in Irish pharmaceutical companies were the lack of finance to train the required personals to handle the program which led to a shortage of qualified manpower. In addition, adaptability to change, team work, the use of multiple tools and management commitment to LSS were identified as the most important facilitators to LSS. To this end, the study concludes that the major barrier to LSS in Irish pharmaceutical companies was a lack of understanding as to what LSS really is due to poor training tried to several other factors
