Over the last decade, stress at work has become a major problem in Europe. A European and national legal framework has been developed and several methods for stress diagnosis and stress management intervention have been identified. Within this context, it is necessary to carry out a systematic examination of diagnosis practices and interventions that take place in companies. The objectives of the study were : 1 / the evaluation of work stress diagnosis practices in Belgian companies, and 2 / the identification of factors that stimulate or block the implementation of stress management interventions. A survey was used to collect data about work stress diagnosis practices. The first objective was explored through qualitative open questions about stress diagnosis and intervention. The second objective was achieved using a specific questionnaire, which was elaborated for the purpose of the study. Based on a review of the scientific literature, this questionnaire assessed the stimulating and blocking factors for implementing stress management interventions. The sample includes 180 Belgian companies of different sizes (from 20 to more than 10,000 workers) and from different sectors of activity. Only one out of six companies had implemented a stress diagnosis. Among those who had done so, only one out of two had implemented actions, and only one out of four had moved onto an evaluation stage. Stimulating factors related to the methodology implemented and the communication process were identified, as well as blocking factors relating to financial and temporal constraints, and the context of change in the company. The latter is a relatively new factor with regard to the existing literature. The discussion includes four points of analysis. The interventions which are implemented are clearly concerned with the primary approach that focuses on the work environment. Secondly, the results support the necessity for a systematic evaluation process of stress management interventions. Moreover, the results offer evidence of a need for sensitisation and publication of best practices about the necessary stages in the stress prevention process, as well as about stimulating and blocking factors. This holds especially true for small-size companies which carry out fewer diagnoses than larger ones. It is also important for companies which are not yet involved in stress diagnosis, and those that are less aware of the impact of financial and temporal constraints.