In her new book, Customers.com, Patricia Seybold cites a marketing breakthrough made by a furniture maker specializing in day-care equipment for special-needs children. He realized that although day care centers wrote the checks for his furniture, the suggestion to purchase often came from physical therapists not employed by the centers.

By targeting these influencers, and making sure they knew of the benefits of his products, the furniture maker increased sales. Here and with other businesses, because each influencer has sway with multiple prospective buyers, establishing a cordial relationship with the influencer can pay off more than directly courting buyers.

For an attorney who performs real estate closings, the influencers are real estate agents and mortgage brokers.

For a psychotherapist who helps women with mid-life issues, key influencers are gynecologists.

For a portrait painter, influencers might be decorators or remodelers.

For a home security company, influencers include builders, condo associations and insurance agents.

For a wine shop, some influencers are caterers, high-end delis and wine stewards at fine restaurants.

Once you identify categories of influencers, you next need to target and woo individuals in that category. Remember that influencers will be passing valued clients on to you. So they must feel personally convinced you will treat their clients well. Thus you need a personal approach, such as by inviting influencers to lunch one by one.

The way you phrase the invitation sets the tone for your interaction. Explain that the purpose of the lunch is getting to know more about their work, since you are in a position to refer clients to them. Of course, unless your opposite number is a complete egomaniac, this means he or she will learn more about you as well.

After your meeting, if you're in a position to do so, refer clients to the influencers. Again, unless they're ungracious dolts, this makes them well-disposed toward you -- and gives you an excuse to interact further. Soon you're great buddies and the influencer wouldn't think of sending clients to your competitors.

Alternatively, you can clinch a relationship with influencers by presenting programs or special events that benefit them. Years ago, a mortgage broker hired me to speak to a breakfast meeting of her influencers. The free seminar and classy yacht-club meal were a way for her to thank those who'd sent her business the previous year and recruit those who hadn't yet referred a home buyer.

Finally, you can win the good graces of influencers who know you by sending them obscure magazine articles concerning their field of business that you've clipped. Attach a note: "Thought you would find this of interest..."

When these tactics yield referrals, there's one more item to take care of, a personal thank-you, and perhaps a gift -- flowers, a book, a restaurant gift certificate, concert tickets. No matter how many referrals have been acknowledged before, the thank-you helps ensure that the largess of your influencer will keep on working in your favor.

Boston-based marketing and publicity consultant Marcia Yudkin is a syndicated columnist through ParadigmTSA, a public radio commentator and the author of nine books, including Six Steps to Free Publicity and Persuading on Paper: The Complete Guide to Writing Copy that Pulls in Business. She also delivers eye-opening, content-rich seminars on publicity and marketing to business and professional groups nationwide.

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