Here is a video produced by the American Dental Association that we think gives an excellent overview of the options available to someone considering teeth whitening. We encourage you to watch this short documentary (approximately 2 minutes).

Of course, consider this was produced by the dental association, so it is clearly skewed in favor of having a dentist do the work. Remember that there are completely at-home systems that don't require a dentist, such as the NovaWhite product.