Most observational methods for musculoskeletal disorder risk assessment have been developed by researchers to be applied in specific situations, and practitioners could find difficulties in their use in real-work conditions. The main objective of this study was to identify the factors which have an influence on how useful the observational techniques are perceived to be by practitioners and to what extent these factors influence their perception. A survey was conducted on practitioners regarding the problems normally encountered when implementing these methods, as well as the perceived overall utility of these techniques. The results show that practitioners place particular importance on the support the methods provide in making decisions regarding changes in work systems and how applicable they are to different types of jobs. The results of this study can serve as guide to researchers for the development of new assessment techniques that are more useful and applicable in real-work situations. Practitioner Summary: A survey about the use of ergonomics assessment methods for identifying risk factors in physical work was conducted among practitioners. The reasons to find a method more or less useful were analysed. The support the methods provide in making decisions regarding changes in work systems and how applicable they are to different types of jobs were found to be the main reasons.