The European Company ( Societas Europaea, SE) regulations include the highest mandatory provision for negotiation of transnational employee voice. What are the effects of transnational employee voice, enacted at works council and board levels, on knowledge exchange within the multinational corporation? This qualitative study of globally active SEs incorporated under the SE regulations that have ‘dual-forum’ transnational employee voice addresses that research gap. Our main contribution reveals that, over time, transnational employee voice facilitates multifaceted knowledge exchange, both widening the platform and strengthening relations for intra-multinational corporation collaboration. Alongside expressing labour interests as intended, dual-forum transnational employee voice stimulates managers and employees to develop mutually beneficial competencies and trust. These aid multilateral knowledge exchange. That knowledge, which includes factors affecting employees and quality of organizational and work life, also includes insights into country-specific market, industrial and operational issues. Importantly, dual-forum transnational voice fosters development of a participatory culture across the multinational corporation. Robust multifaceted knowledge exchange generates better-informed and more productive decision-making that yields plural socio-economic value.