Abstract: A system and method for integrating entities using a graphic user interface (GUI) to provide user-interactive rule-based matching and difference reconciliation. In one aspect, a system for integrating entities employs a combination of default matching and reconciliation approaches and user tailoring to generate a composite entity from one or more input entities using a set of composition rules. The set of composition rules comprises a combination of default rules, as well as rules that represent user interactions that are performed via a graphical user interface when the user edits a composite result. The rules are captured and then stored persistently when the user requests that the composition be saved, such that the rules may be retrieved during a subsequent editing session associated with the same inputs. If the inputs change, the integration process (as specified by the rules) can automatically handle many changes.