Abstract: The invention relates to a method, tool and system for increasing the efficiency of a design process, particularly the capture and reuse of rationale behind design decisions. A tool having an interactive graph editor is used to capture a first design rationale of a first design project, the first design rationale containing data on at least one design issue and a processing means allows the first design rationale to be identified when the at least one design issue is encountered on a second design project. A computer and program are also described and these may be used as part of a system.