Henry has been part of various global, Pan-African and national level campaigns since 2003. He has worked for Oxfam GB in Zambia, covering health and education advocacy; ActionAid International, leading Pan-African advocacy work; and Panos Southern Africa as Programmes Manager for Governance and Development. Henry was also the coordinator of the Zambia chapter of the Global Call to Action and the UN Millennium Campaign, and was actively involved in northern lobbying events, including the G8 and UNGA processes.