1 EXHIBIT 21.0 ORGANIZATIONAL CHART ------------------------------ Trenwick Group Inc. ID No. 06-1152790 ------------------------------ | | ------------------------------------------- | | 100% | | 100% - - ------------------------------------- ---------------------------------------- Trenwick Services, Ltd. Trenwick America Corporation ID No. 06-1087972 - - ------------------------------------- ---------------------------------------- | | 100% | | 100% - - ------------------------------------- ---------------------------------------- Trenwick Guaranty Insurance Trenwick America Reinsurance Corporation Company, Ltd. ID No. 06-1117063 Domicile-Connecticut NAIC Code-34894 - - ------------------------------------- ----------------------------------------