Balancing environmental, social, and economic performance is today considered a key responsibility that firms have toward society. As a result, academics, practitioners, and political decision makers are increasingly paying attention to environmental management systems improving a full spectrum of environmental performance. In that regard, even if recent literature suggests that environmental management should be deployed through a cross-functional approach, extant literature mostly focuses on independent functional systems. This paper addresses this gap investigating how the deployment of environmental management in the human resource function—adopting green human resource management (GHRM) practices—and the supply chain function—adopting green supply chain management (GSCM) practices—impact on environmental and financial performance. We draw from a multiple-respondent survey of human resource and supply chain managers in multiple industries in Italy. The study suggests that GHRM and GSCM impact on both environmental and financial performance and shows that GHRM and GSCM exert those impacts in a joint fashion. Indeed, our results show that GSCM plays a mediating role in the relationship between GHRM and performance. Overall, our results provide researchers and managers with relevant insights into the cross-functional deployment of the environmental values and principles across functions.