Industry-level voluntary programmes are widely practiced as a complementary approach to government law and enforcement in addressing occupational health and safety (OHS) issues. Drawing on insights from institutional theory, this study seeks to explore how companies perceive and respond to voluntary OHS programmes. The setting of the study is voluntary OHS management implemented in the construction industry of Hong Kong. A qualitative research strategy was adopted, combining archive and documentary data analysis and semi-structured interviews. It was identified that 10 groups of industry stakeholders are involved in four categories of voluntary OHS activities. To increase the impact of voluntary OHS activities, a majority of them are co-organised by multiple stakeholders. Contractors experience different levels of institutional or competitive pressures to participate in these activities. The acceptance of a voluntary OHS programme by contractors depends on the power of event organisers, the requirements of project clients and the head offices, the extent to which the programme has been diffused, and perceived effectiveness of the programme. This study contributes to a better understanding of the social processes in which voluntary OHS programmes become accepted by construction companies. The findings provide policy makers feedback on devising and promoting voluntary OHS programmes. Policy makers are suggested to pay attention to the heterogeneous participants in the market. A unified framework might not be effective to all companies.