Multiple-classification ripple-down rules (MCRDR) is an incremental knowledge acquisition technique which preserves the benefits and essential strategy of ripple-down rules (RDR) in handling the multiple classifications. MCRDR, the extension of RDR, is based on the assumption that the knowledge an expert provides is essentially a justification for a conclusion in a particular context. Multiple-classification ripple-down rules (MCRDR) is an incremental knowledge acquisition technique which preserves the benefits and essential strategy of ripple-down rules (RDR) in handling the multiple classifications. MCRDR, the extension of RDR, is based on the assumption that the knowledge an expert provides is essentially a justification for a conclusion in a particular context.