Whether serving on a government commission or a corporate board of directors, the duties of an assistant chairman, also referred to as a vice-chairman, are essentially the same duties the board's chairman normally undertakes. The primary function of an assistant chairman is to complete the tasks and responsibilities of the chairman when the chairman is not available at a meeting or event, or when the chairman directs the assistant chairman to take over.

Presiding

An assistant chairman's main responsibility is to preside over meetings when the chairman is not present. A chairman or assistant chairman must be present for the meeting to fulfill legal requirements. When the chairman is absent the assistant chairman must conduct the meeting responsibly and legally according to the company or organization's articles of incorporation or association.

Putting Forth Motions

Acting as the chairman, the assistant chairman must put forth motions when members of the board are ready to vote on each item discussed during a meeting. These motions must cover only the issues that have been listed on an agenda before the meeting began. Orderly discussion about scheduled items and new issues that arise during a meeting must be maintained by the assistant chairman throughout.

Documentating a Meeting

The assistant chairman must also ensure that all items of discussion, motions and votes are recorded by the organization's secretary. The completion of this duty must be verified at the end of each meeting to make sure discussions, motions and votes are recorded accurately.

Representing the Organization

The assistant chairman is a representative of the organization at every meeting. Therefore, it is her responsibility to keep the organization's best interests at the forefront. This responsibility includes ensuring that all opinions are given fair treatment.

Assisting the Chairman

As her title suggests, the assistant chairman should help the chairman complete each official duty and responsibility as needed. This means taking direction from the chairman. The assistant chairman must have the same authority as the chairman in the chairman's absence, but she cannot override the chairman's direction.