The Board of Appeals shall consist of 5 members appointed by the village president subject to confirmation of the board of trustees for the term of 3 years (such terms shall be staggered so that not more than two terms expire in any one year).  The president shall designate one of the members as chairperson...Vacancies shall be filled for the unexpired terms of members whose terms become vacant.  The president may appoint, for staggered terms of 3 years, 2 alternate members of such board, in addition to the 5 members above provided for.  Annually, the President shall designate one of the alternate members as 1st alternate and the other as 2nd alternate.  The 1st alternate shall act, with full power, only when a member of the board refuses to vote because of interest or when a member is absent.  The 2nd alternate shall so act only when the 1st alternate refuses or is absent.

Appeals to the board of appeals may be taken by any person aggrieved or by any officer, department, board or bureau of the municipality affected by any decision of the administrative officer.

The above description is paraphrased from the Wisconsin Statute 62.23(e)
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