Purpose For employees with a work disability adequate daily guidance from supervisors is key for sustainable employability. Supervisors often lack expertise to guide this group of employees. Mentorwijs (literal translation: Mentorwise) is a training for supervisors to improve the guidance of employees with a work disability. The aim of this study was to investigate the experiences of employees with a work disability regarding: (1) the guidance from their supervisors (who followed the Mentorwijs training), (2) which differences they notice in the guidance due to the Mentorwijs training, and (3) what kind of aspects they consider important in their guidance to achieve sustainable employability. Methods A qualitative study was performed with semi-structured (group) interviews among twenty-one employees with a work disability. Thematic analysis was performed to analyze the data. Results Themes that followed from the interviews were: (1) work tasks and conditions can facilitate or hinder sustainable employability: (2) relationships among employees and with supervisors can affect sustainable employability; (3) a desire for new opportunities and challenges; and (4) a need for supervisor skills to facilitate sustainable employability, i.e. appreciation, availability of help, dealing with problems, listening, attitude and communication. According to employees, changes were mainly noticed in supervisor skills. Conclusions Employees with a work disability were very satisfied with the guidance of supervisors who followed the Mentorwijs training. To improve sustainable employability, training of supervisors should focus more on adequate work conditions, providing employees opportunities to learn new work tasks and improving supervisors’ skills regarding appreciation, attitude and communication.