Soil fertility is at stake at a global scale, putting pressure on food security, poverty alleviation and environmental protection, under scenarios of climate change that in most cases aggravate the threat. In sub-Saharan Africa, a combination of depleted soils and population growth adds particular pressure to smallholder farmers and society. Their capacity to innovate in a social, economic, political and cultural context is seen as decisive to reverse the trend of declining soil fertility. However, many technologies with a potential to protect, maintain and build up soil fertility are hardly used by small-scale farmers, triggering the urgent question on their reasoning not to do so. Exploring and understanding the constraints and complexity of the social systems interacting with the implied institutional dynamics are essential steps in designing appropriate agricultural innovations that are scalable and adoptable. The focus of the inter- and transdisciplinary approach applied in the project ORM4Soil (Organic Resource Management for Soil Fertility; www.orm4soil.net) lies at the heart of this project. We are combining qualitative and quantitative methods from agronomy, sociology and communication sciences in order to bring soil-fertility-enhancing-technologies and their adoption to the center of the decision-making process of farmers’ as well as local and regional institutions. At local and regional innovation platforms, stakeholders from business, government, academia and farmer organizations are discussing the outcomes of agronomic trials and sociological research. We are expecting to create bridges between the needs and concerns of farmers, relevant segments of society and policymaking, with the new common goal to enhance soil fertility