Guillaume began his career with MSF in the late 1990s, where he ultimately managed and successfully implemented programs in more than 25 countries. Later, he served as Lead Buyer for both food and non-food items at both MSF and the ICRC, overseeing portfolios valued at USD 60M per year.

During his time with MSF, and together with UNICEF, Guillaume was a key actor in the establishment of the inter-agency standards for quality management and audit of manufacturers of specialized foods.

In the late 2000s Guillaume led the design, construction, start- up, and development of eight Ready-to-Use Food manufacturing facilities around the world, overseeing building design; the sourcing of equipment and raw & packing materials; supply chain management; implementation of quality management systems etc.

With more than 20 years of manufacturing, supply chain, procurement, and quality expertise, Guillaume is a native French speaker and fluent speaker of English.