Only two metrics matter: ROI from your marketing mix and lifetime value of each of your customers. Forget about clicks, hits, and page views. The Web isn’t a mass-marketing vehicle.

What’s the right marketing mix? You have to make sure that every point of contact — in a store, by phone, on the Web — is completely synergistic. The Web has proven that customers have zero tolerance for fragmented lines of business.

Meanwhile, results do matter. You need to convert new customers into real revenue. The biggest risk to the growth of the Internet is something that nobody had considered until very recently: What if most Net spending simply ends up generating business that companies would have gotten anyway?

In the end, my job is to help the industry prove the positive economic impact of the Internet. For companies even to con-sider cutting back on Internet spending is criminal.

Kathy Biro was director of Digitas until January of this year. Before helping to start Digitas, a $187 million Internet-services firm, she was a senior strategist at its predecessor, the consulting firm Bronner Slosberg Humphrey.