Trade union support is a key pre-condition for effective autonomous worker representation and consultation on occupational safety and health. Using data from a recent study, this paper considers such support in container terminals in two countries with contrasting industrial, economic and labour relations’ profiles – Australia and India. Within globally determined corporate approaches, the study identified distinctly different models of participation and varied extent, reach and focus of external union support. Worker representation and participation arrangements were least well-developed and least effective where the role of organised labour was smallest – and where these arrangements were lacking, workers’ experiences of working conditions and occupational safety and health outcomes were poorer. The paper concludes that national labour relations and regulatory contexts were the main determinant of both the existence and quality of participatory arrangements and that, without conducive contextual influences, terminal operating companies had little place for such arrangements in their corporate occupational safety and health management strategies.