A key feature of a company's safety culture is shared perceptions between managers and employees concerning the importance of safety. The purpose of the study was to assess senior managers' perceptions of the current safety culture in Estonian SMEs from different branches of industry, based on a sample of 463 senior managers. The relationships of different aspects of safety culture and safety management systems, senior managers' and employees' perceptions and attitudes to safety were explored through the deployment of different research measures and methods. In addition, a qualitative approach to assessing safety culture is presented. Studies of eight SMEs included observation, analysis of documentation and semistructured interviews with senior managers and focus group interviews with employees. This paper reports on the empirical examination of the relationship between a safety climate and a safety culture through a knowledge management dimension with a special focus on management of safety knowledge. The results of this study indicate that safety climate has impact on the three dimensions of safety culture, namely, psychological, behavioral and organizational aspects of safety culture. Several specific features of safety and knowledge management, such as management commitment to safety, safety information dissemination, communication and workers' involvement in safety were found to influence the relationship between a safety climate and a safety culture. It is concluded that the development of 'communities of practice' is an effective way for employees to exchange explicit and tacit safety knowledge.