The Mayor is the chief executive officer of the City of Mount Vernon. The person holding this office has the responsibility of overseeing the operation of city departments.

The mayor is chosen by a citywide election for a four-year term. The Mayor has a leadership role in budget-making, authority to organize and reorganize administrative agencies and to appoint and remove their heads, and a strong veto. The Comptroller, elected on a citywide basis for a four-year term, recommends financial policies and advises the Mayor and the City Council in the preparation of the budget.

Legislative authority is vested in the City Council, made up of 5 members, who are elected for four-year terms. The presiding officer is the Council President. He or she is elected for a one-year term at the statutory meeting of the City Council (first public meeting of the year). The Council President is the spokesperson for the City Council and appoints the heads of the various Council committees to one-year terms. The Council introduces and enacts all laws and approves the budget and it can override a mayoral veto by a vote of four-fifths of all the members.

The Board of Estimate and Contract is the arm of local government that grants approval for spending that is not within the jurisdiction of members of the electorate separately. The Board is composed of the Mayor, the Comptroller and the President of the City Council. In order for expenditures to be approved by the Board of Estimate and Contract it must be passed by a majority of members. Legislation is then enacted authorizing the expenditure. The Board of Estimate and Contract convenes following meetings of the City Council.