Organisations have started to acknowledge that employee stress and well-being have a central role in organisational performance and can also impact individuals’ overall health. Poor employee well-being and stress have been linked to psychological, physiological, and behavioural issues such as loss of productivity, work accidents (Fries, 2009), cardiovascular disease, hypertension (Tennant, 2001), and increased staff turnover (Murphy, & Sauter, 2003). Furthermore, distress can decrease life satisfaction and have a major influence on our daily lives (Berger, 1994). Employee well-being programmes became popular in the 1970s, such as the programme developed by Jon Kabat-Zinn which is known as the ‘mindfulness-based stress reduction’ intervention. In this meta-analytic study, the effect of MBSR interventions categorised in three groups (tMBSR, mMBSR, and cMBSR) on employee stress and well-being is examined. Statistical data of stress levels was taken from the following measures: GHQ, DASS, MBI, and PSS. Statistical data of well-being levels was taken from measures such as the SPWB, the SWLS, the SF-36 and the SF-12v2, and the PSQI. The meta-analysis on MBSR and its effect on stress reduction resulted in a medium summary effect size (g= -0.489). A smaller summary effect size (g= -0.242) was found when carrying out a meta-analysis only comprising of studies which included a control group. The meta-analysis on the effect of MBSR on enhancing well-being outcomes resulted in a moderate effect size (g= 0.512). The findings in this study are in line with previous research outcomes supporting the claim that MBSR assists in stress reduction and increases well-being in employees. There are various limitations to this study such as few controlled studies and a majority of samples working in the health care sector. Future research could focus on cMBSR interventions in the workplace and explore why they may have a larger effect size than traditional MBSR.