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                                                                    EXHIBIT 10.4

                              DIRECTOR'S AGREEMENT

     This Agreement, dated as of September ___, 2000, is between FRONTIER
FINANCIAL CORPORATION, a Washington corporation ("Frontier") and [FirstName]
[LastName] ("Director"), a director of Interbancorp, Inc. and Inter Bank
(hereinafter referred to jointly as "Interbancorp").

                                    Recitals

     1. Pursuant to the terms of the Plan and Agreement of Mergers, dated as of
September __, 2000 (the "Plan") between Frontier and Interbancorp, Interbancorp
will become merged with Frontier, with Frontier as the surviving corporation.

     2. Frontier's obligation to consummate the transactions contemplated by the
Plan is conditioned upon their receipt of non-competition agreements from all
directors of Interbancorp.

     3. Director is both a director and a shareholder of Interbancorp.

                                    Agreement

     In consideration of Frontier's performance under the Plan, Director agrees
that for a period of two years after the Effective Date, as defined in the Plan,
he or she will not, directly or indirectly, become involved in, as a principal
shareholder, director or officer, "founder," employee, or other agent of, any
financial institution or trust company that competes or will compete with
Interbancorp, Frontier, or any of their subsidiaries or affiliates, within a
thirty-mile radius of the Main Office of Inter Bank.

     Director also agrees that during this two-year period, Director will not
directly or indirectly solicit or attempt to solicit (1) any employees of
Interbancorp, Frontier, or any of their subsidiaries or affiliates, to leave
their employment or (2) any customers of Interbancorp, Frontier, or any of their
subsidiaries or affiliates to remove their business from Interbancorp, Frontier,
or any of their subsidiaries or affiliates, or to participate in any manner in
any financial institution or trust company that competes or will compete with
Interbancorp, Frontier, or any of their subsidiaries or affiliates, within
Washington State. Solicitation prohibited under this section includes
solicitation by any means, including, without limitation, meetings, telephone
calls, letters or other mailings, electronic communication of any kind, and
internet communications.

     For purposes of this Agreement, the term "principal shareholder" means any
person who owns, directly or indirectly, five percent (5%) or more of the
outstanding shares of any class of equity security of a company.

     Director recognizes and agrees that any breach of this Agreement by
Director will entitle Frontier and any of its successors or assigns to
injunctive relief and/or specific performance, as well as any other legal or
equitable remedies to which such entities may otherwise be entitled.

FRONTIER FINANCIAL CORPORATION              DIRECTOR


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Its:
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