The St. Mary's Vestry consists of nine members elected by the parish members at the Annual Parish Meeting in January of each year to serve three year terms of office. Vestry members must be regular in attendance at divine worship, able to attend monthly vestry meetings, not be related to any other members of the vestry; express Christian stewardship by being a pledging and fulfilling member of the parish; and actively support the policies and programs of St. Mary's.
The Vestry meets on the 3rd Sunday of each month at 11:30 AM in the Hirst House and decides issues relating to the business and financial matters of the parish, establishes written operating policies for the church, employs and periodically evaluates the Rector, and ensures compliance with Diocesan policies.
A Senior Warden is selected from the Vestry members at the first meeting of the year. This person serves as the chief administrative officer of the parish and is the primary advisor to the Rector in parish matters.