Information is a key feature that health professionals need to exercise their profession with efficiency and quality. This study aims to present the experience of the usage of an electronic system for clinical documentation in nursing in a university hospital. It is a methodological research of technology production. The system was developed in four phases: Conception, Elaboration, Construction, and Transition, and was named Electronic Documentation System of the University of São Paulo Nursing Process (PROCEnf-USP™). The knowledge base of PROCEnf-USP™ was organized in hierarchy of domains and classes, according to NNN linkages.