The long-term impact of role stress (conflict and ambiguity), cognitive rumination and their interaction were analysed upon morning and evening saliva cortisol secretion. The sample consisted of 52 male and 24 female British white-collars who had participated in a survey study on psychosocial working conditions 3.5 years earlier. Saliva cortisol secretion was measured over seven consecutive days with two measures: in the morning on awakening and at 22.00 hours. Stepwise linear multiple regression analyses was used for the statistical analyses. Role ambiguity at baseline and the interaction between role ambiguity and trait rumination contributed to explaining elevations in morning saliva cortisol secretion 3.5 years later (R(2) = 0.045; F = 4.57; p < 0.05), while role conflict at baseline significantly predicted increases in long-term evening saliva cortisol (R(2) = 0.057; F = 8.99; p < 0.01). The findings support a long-term relationship between chronic stress exposure and saliva cortisol secretion and some support for the assumption of cognitive rumination moderating the stressor-strain relationship. STATEMENT OF RElevance: The study is of interest for ergonomics practice because it demonstrates that work role ambiguity and role conflict, typically associated with organisational downsizing and restructuring, may contribute to long-term psycho-physiological reactivity. This could expose workers to increased health risks. Therefore, stress management programmes should include the concept of role stress, especially at a time where many work organisations are undergoing significant change. Management should also be made aware of the importance of communicating clear goals, objectives and lines of authority as well as providing sufficient training for those in new job roles.