While a lot has been done to understand the use of comparative advertisement to sell consumer goods such as cars or soaps, we have no knowledge of the effectiveness of comparative advertising of professional services such as health care or legal services. In this paper we report the results of a study designed to measure the effectiveness of comparative advertisements of professional services using recall measures and consumer attitude towards the ad. The main conclusions were that the recall of comparative ads of professional services is comparable to recall of comparative ads of consumer goods; however, consumer attitude towards comparative ads of professional services is significantly lower than consumer attitude towards all other types of ads.