Joost started his career in international development, working for the World Bank, UN and a range of bilateral donors across the world: Washington DC, China, Afghanistan and Bangladesh. Before that he obtained an MA with honors in International Relations and Economics from the Johns Hopkins University School of Advanced International Studies (SAIS) on a Fulbright Scholarship, and an MA in History from the University of Amsterdam. This varied background has shaped his working perspective, focusing on the context of sustainability issues.

Joost has been involved in the initial phase of several sustainable market transformations, principally in agri-commodity sectors such as coffee, cocoa and cotton and currently palm oil. He has helped structure sector-wide coalitions that have transformed the entire sector towards more sustainable practices, and has continued to work with these coalitions to design strategies that can scale-up their potential. Joost supported the Sustainable Coffee Program as interim manager throughout its development phase, and did so again after its merger with the 4C Association to form the Global Coffee Platform. He also managed the start-up phase of CocoaAction with the World Cocoa Foundation,  as well as for the Organic Cotton Accelerator  with a group of companies and foundations. The past years he also led the development of an analytical approach focused on Service Delivery Models for IDH, which brought key companies to share their challenges and successes in reaching smallholder famers and work on improving their models jointly. He is currently working on uniting global and local stakeholders around a transformative landscape approach in the Palm Oil sector with RSPO: certifying jurisdictions instead of value chains.