Abstract: Diagnosis and procedure terminology are ontologically organized according to context-based categories and medical concepts. The medical concepts are linked to aliases and medical codes used to document patient care. A user is guided to select and document additional medical concepts based on a medical concept dependency that has been created between certain medical concepts, some of which are required. A visual concept tree presents for user consideration all categories and medical concepts necessary to determine appropriate medical codes based on the disease, condition or injury in accordance with a ranking algorithm and user documentation preferences. Potential medical codes are also optionally presented for user consideration based on collected documentation and selected medical concepts.