Good news. A report produced by brand consulting firm Blueprint Communications says most marketers prefer to combine their advertising agencies with unrelated PR firms to achieve integrated marketing success, rather than relying on the resources of a single holding company that has PR, advertising, and other disciplines conveniently located under one roof."Why is this good news?" I hear Martin Sorrell, David Bell, and John Wren asking. It might not be good news for them, since they would all, to one extent or another, like to believe that offering a smorgasbord of marketing services under one roof enables clients to realize synergies. What that means to clients, for the most part, is that they can save money. But they can only do so by sacrificing quality for convenience. That's because the likelihood of finding the best possible ad and PR agencies (and the best possible sales promotion agency and the best possible direct marketing expert) under a single umbrella are slim. A trade-off has to be made. Ogilvy & Mather might have presented the best advertising ideas, and Ketchum might have presented the best PR ideas, but because the client company wants an "integrated" agency, it'll go with Ogilvy & Mather and a sister firm. That's disheartening for a couple of reasons. First, if PR firms don't win business on their own merits, but rather on those of their advertising sister companies, they'll soon deserve the second-class status they currently enjoy within holding companies. Second, and more important, there are reasons why a client shouldn't get PR and advertising advice from people who are employed by the same company. Let's say you're a client with a crisis, and you want to know how to address it. If you work with an independent ad agency and an independent PR firm, the ad agency might come in and tell you the solution is to run a major advertising campaign: full pages in The Wall Street Journal and The New York Times, TV spots during the Sunday morning shouting matches. The PR firm, on the other hand, might tell you that would be a waste of your money. Instead, you should meet with a couple of key opinion leaders, reach out to the activist groups, perhaps even change the way you operate. Now imagine you work with a PR firm and an ad agency that both belong to the same holding company. Sure, there's a chance the PR firm might still tell you to kill the ad campaign, but don't bet on it, not if it wants to keep the job or keep getting accounts handed to it on a platter by the ad agency. Sometimes, conflicting advice is healthy. Paul Holmes has spent the past 16 years writing about the PR business for publications including PRWeek, Inside PR, and Reputation Management. He is currently president of The Holmes Group and editor of www.holmesreport.com.