The Workload Control (WLC) concept is one of few Production Planning and Control (PPC) solutions appropriate for Make-To-Order (MTO) companies yet its successful implementation is an enduring challenge. Most implementations reported are in large organisations yet it has been argued that WLC is particularly suitable for Small and Medium sized Enterprises (SMEs) with limited financial resources. Moreover, previous studies do not adequately describe the process through which implementation success was achieved. In this paper, data collected through semi-structured face-to-face interviews with key personnel from 41 companies is presented in order to build up a body of evidence on the characteristics of MTO SMEs that affect WLC implementation. The data paints a complex picture of MTO production and suggests that research is likely to be required to move theory closer to practice and organisational change to move practice closer to theory. The former is recommended where processes perform well or appear difficult to change; the latter is recommended where fundamental WLC principles are involved. Two outputs emerge from the study: (1) a research agenda for refining the WLC concept to improve alignment between theory and practice, covering the customer enquiry, order entry, design and engineering and order release stages; and (2) an implementation strategy, including elements of organisational change and covering pre-implementation, implementation and post-implementation stages. The characteristics of MTO SMEs identified should be used in future research to develop more realistic simulations for testing conceptual refinements while field research should apply and extend the implementation strategy presented in order to develop a more detailed roadmap for successful WLC implementation in practice.