Professor Sellen’s core interest is understanding how the evolved feeding and care needs of human infants and young children can be met in today’s rapidly changing world. His theoretical work has explored the relevance of concepts and theories in human ecology, evolutionary biology and medical anthropology to global public health efforts to optimize young child feeding and care practices. He currently leads or contributed to several global health research partnerships that apply implementation science techniques to develop and test community-level innovations to protect, support and strengthen nutrition and care of infants, children and vulnerable caregivers, primarily in low income countries. Recently funded projects focus on gender oriented and pro-poor innovation, design, implementation and evaluation of programs aimed at healthy infant and young child feeding, smallholder value chain addition for nutrition security, and mHealth capacitation of maternal, neonatal and child health extension. He has also initiated studies of food insecurity and child nutrition among refugees in Britain, America and Canada.