Health care organizations in Sweden are recently reorienting toward horizontal organization around care processes.  The aim was to investigate how implementation approaches for improvements of care processes in line with lean production (LP), at strategic and operative levels, in hospitals are associated with the consequences for working conditions and stress-related health among the employees. Five hospitals working with improvements to care processes were tracked: questionnaires to employees (n=1326) and interviews at strategic and operative levels at baseline and follow-up. The process redesign implementation strategies varied between the strategic and operative levels. There were associations between a higher degree of LP at operative level and increased work resources and decreased work demands. Physical, cognitive and mental stress-related symptoms were only weakly associated with strategic or operative LP initiatives. There was evidence of more beneficial or improved working conditions in relation to strategic or operative initiatives, approaches to degree of LP.