This article reports the results of a case study that sought to investigate the prevalence of work-related musculoskeletal disorders (WMSDs) in three different sectors in Portugal: administrative services, services for the elderly, and services for children. In methodological terms, a combination of tools and instruments was used, with emphasis on the application of a questionnaire (adapted to each sector under study) and the application of WMSDs risk assessment methods (such as REBA and mRULA). In this study, 85.3% of the invited participants signed up (completing the questionnaire applied) and 32 postures were analyzed to determine the level of risk of the tasks associated with the various sectors. This article focuses on the results obtained with the questionnaire. More than 50% of the operators had a high prevalence of self-reported musculoskeletal symptoms, with pain reported in the lumbar (80.6%), cervical (75.5%), dorsal (62.2%), and shoulders (53.1%); an analysis by sector highlights the same body regions. The results show a positive association between the demands of the job and the symptoms reported, highlighting the urgent need for interventions to improve working conditions in the sectors analyzed.