Kontoma joined the Oxfam GB Programme in 2006 as a cash transfer supervisor for three months, before becoming a Public Heath Community Mobilizer for two years. He then moved to the Hunger Safety Net Programme as a Project Officer for four years and went on secondment to Somalia as the Deputy Emergency Food Security and Livelihoods Coordinator, working closely with partners during the emergency response for 6 months. When he returned to Kenya, he worked as the Agriculture Programme Coordinator for the Turkana Programme, before going back to Somalia on secondment again as the Food
Security and Livelihoods Manager for a year. Since 2013, he has been the WASH Advocacy Manager for Oxfam in Kenya, based in Wajir, working with the County government and local partners. He has a passion in community engagement, influencing and advocacy work.