Increased pressure for labour market flexibility and increasing demand over workers' performance have fostered the idea that working conditions, in most European countries, have progressively deteriorated with adverse effects on psychological well being and mental health. This paper investigates the links between contractual arrangements, working conditions and mental health using time-series cross-section data for 15 European countries. We use different waves of the European Working Conditions Survey (1995, 2000, 2005) to document recent patterns in mental health at the workplace and to assess how these are related to various job attributes. We find substantial heterogeneity in mental health incidence at the workplace both across workers, as well as between countries. Given population heterogeneity in responses to mental health questions, we implement a methodology for differential reporting in ordered response models which allows for threshold shifts. We show that a set of workplace attributes, such as: working in shifts, performing complex and intensive tasks and having restricted job autonomy lead to a higher probability of reporting mental health problems. We also provide evidence of a positive causal effect of adverse overall working conditions on mental health distress. We show that labour market institutions, and health and safety regulations can explain a significant part of cross-country differences.