Service robotics has been an active research and development area for more than ten years. However, most of the subsystems needed to create a fully operational service robot have been developed separately by individual research groups. Modularity could be the key factor to success by reducing the development time and by increasing the technical advancement level. Thus, it could directly help to gain significant savings on the total development costs. The reliability of the subsystems would also be improved, because more time and money could be used for that. Modularity, and especially the work with standard interfaces, would also make the modification of these robots much easier. The case study in which the concept of modularity has been studied is that of the WorkPartner robot. This is an advanced service robot, in which most of the important modules in service robotics have been integrated together successfully. The utilisation of modularity in this project was essential due to the high hardware and software complexity of the robot required to complete the given working tasks. This case example also demonstrates very clearly that significant savings in the development time and costs could be gained if commercial modules for service robots were available. Standardisation work is needed for boosting modularity. If the interfaces of the modules could be standardised, this would create a far better operational environment for the current and future module producers. Safety standards are required before more generic service robots can be released to the wider market. Currently, there are safety standards for industrial robots and automatic forklift trucks, but these standards would require at least a considerable amount of modification before they could be more widely applied to the field of service robotics. Modularity is clearly essential for the successful development of reasonably priced service robots. Right prices will boost the demand for service robotics and that, in turn, will direct more effort to service robotics development in general, and thus a positive cycle would evolve. One could safely state that modularity will be one of the key factors that is required to guarantee that the service robotics industry will reach global success in the near future.