Objectives The aim of this study was to (i) explore promoting factors for sustained return to work (RTW), according to vocational rehabilitation professionals (VRP) that are amenable to change for employees who have been on sick leave >18 months and (ii) gain insight into crucial aspects of interventions.Methods Semi-structured interviews were carried out with 23 VRP. All interviews were transcribed fullyverbatim. An inductive analysis of the transcripts was performed, using a process of identifying, coding, and categorizing the primary patterns in the data.Results Key influenceable promoting factors for sustained RTW by long-term sick-listed employees include:employee-based vocational guidance; integral, effective communication between the sick-listed employee and all RTW stakeholders; personal factors; a supportive work environment; and a stimulating social environment. Crucial aspects of interventions include: gathering information and setting priorities; improving qualifications; influencing cognitions; monitoring the sick-listed employee through the rehabilitation process; offering tailormade interventions at different stages within a personal time-bound action plan; and preparing the employee and the work environment for RTW.Conclusions Sustained RTW for long-term sick-listed employees can be achieved by focusing on the influenceable promoting factors for RTW. The use of combined interventions in a holistic approach involving the worker and his environment is considered the best way to address the multicausality of work disability and could help maximize RTW outcomes.Key terms long-term sickness absence; return-to-work facilitators; RTW; RTW coordinators; sickness absence; work disablement; work rehabilitation. [E-mail: p.m.dekkers@amc.uva.nl] Long-term sick leave is a major socioeconomic problem in Western countries due to the enormous financial costs for society (1). Several studies have shown the importance of the return-to-work (RTW) transition process for employees on long-term sick leave (2-4). Early research has shown that the probability of RTW decreases as the duration of sick leave lengthens (5). Achieving early job reintegration of chronic work-disabled employees is a difficult goal to accomplish due to the complexity of factors involved, and the issue needs ongoing attention.An employee on long-term sick leave is an individual who functions in a complex context in which different factors can play a role, such as medical, personal, environmental, or work-related factors (6). These factors can either perpetuate sick leave or promote RTW (7) among employees who have been sick-listed for >1.5 years; the factors that stimulate RTW may be different from those that facilitate a sustained RTW. Some promoting factors for RTW are potentially influenceable and could offer opportunities for health professionals to improve work participation. Therefore, stimulation of these positive factors is important to facilitate work resumption of employees on long-term sick leave.There are several important actors...