Often professional service firm principals tell me they are frustrated with the quality of their marketing materials, they are concerned with their firm's low profile or they feel pressure because their efforts are not generating enough new client leads. Are any of these issues for you?

Many professionals do not know there is a body of knowledge about what does and does not work in marketing professional services. A review of the marketing recommendations of Maister, Robert Bly, Alan Weiss and other experts reveals a recurring theme of what does and does not work in professional service firm marketing. My own 20 years of practical experience in marketing professional service firms supports these findings.

The best marketing for professional service firms is educational in nature. Here are the top 14 tactics that work, in order from the least to the most effective:

The inadequate seven

14. Cold calling -- This should be done by a business development person, never a principal. Nothing says "trust me" like a cold call. A better approach is what I call warm calling, which is following up with seminar invitations.

13. CD-Rom or video brochures -- These can be great lead conversion tools, but they cost too much for lead generation. Instead, stick the videos on your Web site.

12. Printed brochures -- Again, don't spend too much money up front to generate leads. Instead, create these as PDF files that Adobe Acrobat can read, and place them on your Web site.

11. Sponsorship of cultural/sports events -- Being title sponsor of the right event can have an impact, but it is not the best use of lead generation dollars.

10. Advertising -- Isn't it ironic that none of the great advertising agencies built their clientele by advertising? However, if you specialize in an industry and they publish directories, it is always good to have your firm included.

9. Direct mail -- This is the traditional direct mail of a letter and a printed piece, like a response card. Some accountants and financial planners have used this cost effectively, maybe offering a complimentary consultation (there is a much better form of direct mail; see tactic No. 1).

8. Publicity -- While getting your name in the newspaper and trade journals is a cost-effective way to increase awareness about your firm, it doesn't always translate into leads.

The magnificent seven

7. Paid ballroom seminars -- Rent out the ballroom at the local Marriott or Hilton and charge for an all-day or half-day seminar. Participants should take away a substantial packet of good information from your firm (and a good meal, too).

6. E-Newsletters -- This is the water drip torture school of marketing and the opposite of Spam. By signing up for your newsletter lists, prospects are telling you that they are interested in what you have to say but not ready for a relationship now. These people should receive valuable how-to information and event invitations from you on a monthly basis until they decide to opt-out of the list.

5. Networking and trade shows -- An excellent way to gather business cards and ask for permission to include them on your e-newsletter list.

4. Community and association involvement -- Everyone likes to do business with people they know, like and trust. You need to get involved and "circulate to percolate," as one Ohio State University professor used to say.

3. How-to articles in client-oriented press -- Better than any brochure is the how-to article that appears in a publication that your target clients read.

2. How-to speeches at client industry meetings -- People want to hire experts, and an expert by definition is someone who is invited to speak. Actively seek out forums to speak and list past and future speaking dates on your Web site.

1. Free or low-cost small-scale seminars -- The best proactive tactic you can employ is to regularly invite prospects by mail and e-mail to small seminars or group consultations. If your prospects are spread out geographically, you can do these briefings via the Internet (Webinars) or the telephone using a bridge line (teleseminars). These can't be 90-minute commercials. You need to present valuable information about how to solve the problems that your prospects are facing, and then a little mention about your services.