Another method of obtaining expert advice on promotion is to employ the professional services of public-relations experts. Usually these experts do not charge for handling newspaper advertising, since in most cases they receive a commission from the publishers. They can be very helpful, in addition, in increasing the effectiveness of the direct-mail and publicity campaigns, at relatively small cost. Not only can public-relations experts bring creative ideas and skilled services to the promotion campaign, but their experience with other situations can help to make estimates more accurate and errors less costly.