The purpose of this study was to explore the relationship between employees’ work performance and their well-being, job satisfaction, and life satisfaction in sedentary jobs in Slovenian enterprises using a mixed-methods research design. The quantitative component of the research included the responses to four selected questionnaires of 120 employees in 22 identified enterprises (out of 81), with more than 20 employees, having more than 85 percent sedentary jobs. Each of four questionnaires was chosen to cover one area of enquiry under the research foci of work performance, job satisfaction, life satisfaction and well-being. The statistical program STATA was used for data analyses. The analysis shows statistically significant positive correlations between employee performance and job satisfaction (r = 0.35), employee performance and life satisfaction (r = 0.28), life satisfaction and well-being (r = 0.33), and job satisfaction and well-being, whereas the correlation between well-being and work performance did not prove to be statistically significant. The qualitative component of the mixed-methods research design included systematic observation combined with one-to-one discussions. The results indicated that job satisfaction and life satisfaction are more significant in determining work performance in sedentary jobs than employee well-being and that being unwell is still considered a sign of weakness; therefore, employees who are unwell do not want to expose themselves and refuse to cooperate in activities and studies about well-being. Further research examining the impact on work performance of organizational climate measurements in sedentary jobs is recommended.