A fireplace can often ad value and charm to a home, but a poorly equipped fireplace (i.e. one without a good chimney damper) can impair your home's ability to regulate temperature. Unless a damper is secured and closed when the fireplace is not being used, any air you are using to heat or cool your home is essentially being wasted like leaving a window open! In addition to a top-notch damper, consider the following items:
1. An outside intake to the firebox - this allows for the fireplace to pull its combustion air from outside, vs. pulling heated air from your living room.
2. Adding glass doors to your fireplace area is another way to increase the draw of air from outside and the glass front will actually help the fireplace radiate heat into the house.