Gennaro Mattiaccio's small private-eye business started out as many entrepreneurial ventures do: in his own home, with one business phone that didn't ring very much.

And although Richmond Group International, based in Woodbridge, grew steadily in its first four years, Mattiaccio knew his company needed a kick to compete.

Enter the Internet -- the instrument that put the "International" in the company's name. The company's embrace of the World Wide Web provides an object lesson in how the Internet is changing even the smallest service businesses in the Washington area.

RGI, as the company calls itself, was founded in 1992 by Mattiaccio. It provides a range of investigatory services, including employee background checks, asset searches and threat assessments.

Before the Net, the investigative firm's 12 to 13 clients, all based in Prince William County, consisted of small business owners who had caught a glimpse of a small ad in the Yellow Pages, had their hands on Mattiaccio's card or had heard about his business through word of mouth. The RGI work force consisted of about his business through word of mouth. The RGI work force consisted of Mattiaccio and his secretary. Annual revenue totaled about $45,000, he said. And most days were spent searching for customers.

But since Mattiaccio got a Web site in 1996, RGI's client roster has grown to "well over 100," he said. And the demographics have changed as well: Clients come from countries throughout the world, including Peru, Chile, Nigeria, China, Germany and Spain.

The staff has grown to nine full-time and six part-time employees in Woodbridge, and Mattiaccio is trying to hire up to 40 more. RGI has opened a Dallas office with four employees and is about to open another in Chicago with the same number.

Last year's revenue totaled more than $500,000, while the revenue from business brought in over the Internet is expected to exceed $240,000 this year, he said. And now most days are spent contacting -- mostly by e-mail -- investigators and clients around the world. The Web site costs RGI just $120 each quarter.

RGI's experience is one example of how the Internet is helping many small businesses by both expanding the universe of potential customers and providing new tools for conducting business at lower cost.

"I started the company not thinking beyond Prince William," said Mattiaccio, a former special agent with the Criminal Investigation Division of the Defense Department. "But I found that if you can't support clients in other areas, you can't compete."

Now, when someone surfs the Web using keywords such as "missing person," "background investigations" and "corporate security," among others, RGI's home page may appear. Mattiaccio said his Web site gets 20 to 30 hits per day.

"Before the Internet we served the local [county] and region. After, we're serving Paris, Japan, South Africa," he said.

For RGI, the Internet also serves as a powerful, efficient and low-cost means for conducting the various types of investigations the company offers.

For threat assessments against a company or high-level employee, for example, RGI often looks to the Internet chat rooms related to the corporation to see what is being said about the client. Often, RGI can develop leads and information about a company's products or personnel through a chat room or an online "water cooler" where employees openly talk about their company.

Sometimes, Mattiaccio said, a company's competitors use the Internet to disseminate negative information about a service or product, and again, RGI can easily investigate the information using the Internet.

RGI also is often asked to do background checks on job candidates for executive positions. On one recent assignment, portions of the investigation had to be conducted in Germany, Australia, Hong Kong and Poland.

On such projects, RGI can use the Internet to hire investigators in those countries to complete different parts of the background check -- interviewing references, reviewing police records or verifying resume information.

Mattiaccio said of the recent multinational assignment, "Without the Internet, we would not have been able to complete this investigation in the 30 days we were allotted."

Potential clients also can use the RGI Web site to inquire about the cost of the company's services. RGI then provides an estimate by e-mail.

Mattiaccio can complete entire cases without ever talking to the client. "I would hate to think what our phone bill would be" without the Internet, he said.

With the Internet, small companies are now able to cut expenses that might have drowned start-ups in the past, said Julian Lange, professor of entrepreneurship at Babson College in Boston, who studies the effect of the global computer network on small businesses and entrepreneurs.

Lange cites, for example, the ability for a small business to provide customer services on the Web site, such as answering frequently asked questions. "It just cuts costs in the long run for the smaller firm," he said.

"One of the things about the Internet: It's changing so dramatically, so quickly. Nobody knows for sure how it's all going to play out, but it gives a significant advantage to small companies," said Lange.

Mattiaccio agrees, and says about RGI's growth, "It would have been impossible without the Net."