BASSWOOD PARTNERS, L.P.

                                                                    Exhibit (3)

                                    AGREEMENT

          The undersigned agree that the attached Schedule 13D relating to the 
Common Stock of NSS Bancorp (amending the Form F-11 previously filed with
respect to the Common Stock of Norwalk Savings Society, the predecessor of
NSS Bancorp) shall be filed on behalf of the undersigned.

Dated:  January 2, 1998

                                    BASSWOOD PARTNERS, L.P.

                                    By: Basswood Management, Inc.,
                                        its General Partner


                                    By:   /s/ Xxxxxxx Xxxxxxxxxx      
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                                         Xxxxxxx Xxxxxxxxxx, President



                                       /s/ Xxxxxxx Xxxxxxxxxx      
                                    ----------------------------------
                                          (Xxxxxxx Xxxxxxxxxx)



                                       /s/ Xxxxxxx Xxxxxxxxxx      
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                                          (Xxxxxxx Xxxxxxxxxx)


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