The concept of sustainable development is commonly used worldwide. In the public sector, characterized by a rationalization focus, conclusions about the sustainability of lean production (lean), as a management concept for organizational change, are contradictory. This thesis aims to identify conditions promoting sustainable development in the public sector, in particular the healthcare sector, when implementing lean. Two qualitative and one quantitative case study were conducted using longitudinal data collection: focus group interviews, semi-structured interviews, analysis seminars, steering board meetings, and a questionnaire. The empirical data was collected from national lean programs in Sweden. The results describe that socio-technical principles may be used as indicators of sustainability as well as a guide in the implementation of lean in healthcare. Active ownership among stakeholders, a developmental view in the organization, stakeholder participation, organized joint innovative learning activities, role and goal clarity may be conditions influencing the sustainability of lean in the public sector. Furthermore, when supported by a favorable lean context, the results show that the lean tools value stream mapping, standardized work and 5S (housekeeping) may promote a sustainable implementation of lean in healthcare by the promotion of employees and managers’ working conditions and/or employee individual innovation. Visual follow-up boards may inhibit employees and managers’ job satisfaction, when not supported by job resources. Personnel stability, time for development, and information to be able to participate were in this context shown to be central job resources. In conclusion, conditions which may promote sustainable development in the public sector, when implementing lean are: stakeholder values of inclusive social well-being, an implementation process including stakeholder ownership and joint innovative learning, and a favorable lean context: balancing job resources and job demands. Lean tools may empower public healthcare employees to engage in development and counteract a poor implementation process and a poor lean context but only to a limited degree. The lean contexts studied were unfavorable, i.e., a weak implementation process and job resources not balancing the job demands. Hence, the lean implementations studied could not be considered sustainable.