Everyone in the Hills-of-Skyline area of Wilmington, DE, knew Tom and Bonnie Bentley's five sons when they were growing up. Keith, Barry, Greg, Scott, and Ray were popular, industrious, and good students.

They shared the same paper routes. They all worked at Wassam's variety store. They built go-carts. Two were Presidential Scholars at John Dickinson high school in successive years, while two others were on the wrestling team. They were often together, so no one was surprised when the five brothers started a business.

Bentley Systems, Inc., founded in 1984, sprang from their shared love of computers, programming, and working together. Today, the Exton, PA, company's flagship product, MicroStation(R), has over 200,000 users with full licenses, and Bentley is the second largest developer of PC CAD software, after Autodesk. Revenues from MicroStation, which is used in mechanical, architectural, construction, plant, process, and mapping applications, exceeds $100 million annually, and are growing at better than 20% a year. First half 1995 Bentley sales were triple the first half of 1994.

The reasons for its success: Broadly, it's the company's strong technical vision, says Bruce Jenkins, of the Cambridge, MA, research firm Daratech. Now that the company is marketing MicroStation under its own name instead of exclusively through Intergraph Corp., its revenues should grow even more, he says. First-half 1995 results bear that out.

President Greg Bentley cites the software's features, particularly its ease of use, as a primary reason for its popularity. "MicroStation was the first PC CAD product with a complete graphical user interface," he asserts. "And, it has the same look and feel across all platforms." He says the software requires 30-40% fewer mouse clicks, which means users can get more work done faster.

Customers agree, but add another reason for the success of MicroStation. "They treat us all like we're part of the family too," says Marco Wo, senior designer at Item New Product Development, Providence, RI. "If we ever have a problem, we just call them. Sometimes we just chat."

Family roots. CEO Keith Bentley, an electrical engineer, first wrote the software that was to become MicroStation in 1982 for DuPont. His objective was to develop a CAD product that would enable the company to do physical and chemical plant designs and schematics on machines other than expensive, dedicated hardware. The product, which Bentley called PseudoStation, emulated the VAX-based Interactive Graphics Design System from Intergraph Corp. on generic terminals. Eventually, DuPont let Keith commercialize the software.

Meanwhile, brother Barry was finishing his Ph.D. studies in chemical engineering at the California Institute of Technology, and running a company he co-founded (Dynamic Solutions Corp.) to develop software for the laboratory chemistry market. He and Keith joined forces in a new company (Bentley Systems) in 1984 to further develop and commercialize PseudoStation as a new product for IBM-compatible PCs. It wasn't long before sales of MicroStation, the name they gave the enhanced product, overtook sales of the laboratory instrumentation software, so they sold Dynamic Solutions to Millipore, Bedford, MA, and concentrated on the new product.

In 1987, Scott joined as vice president of operations and sales and Ray came on board with responsibility for 3-D and rendering functionality and, ultimately, the MicroStation solids modeler.

Initial users, besides DuPont, included Renault, Molex, and others who used the software for machine tooling, among other applications. But, it became apparent to the founders that further growth would depend on marketing prowess they didn't have. "At the time, it was a company of programmers who never worried about sales," says brother Greg. In 1987, Integraph bought 50% of the company and exclusive sales and marketing rights. "Intergraph users had been seeking out MicroStation," he says, "so Keith and Barry saw the liaison with Intergraph as mutually beneficial."

In 1991, Greg joined the other four brothers after selling his own financial software company, Devon Systems. In 1995, the brothers consolidated MicroStation development, marketing, and sales at Bentley.

"Our original vision was to bring to engineering easy-to-use graphics and modeling that didn't depend on an expensive proprietary platform," asserts Greg. "Now, we've done it with five products, and all are hardware independent." Along with Unix, he says, Bentley was the first to support Windows NT, and its products also run on Macs and OS/2.

Early in 1995, Bentley shipped three new products: MicroStation Modeler(TM) a solids modeling product; MicroStation PowerDraft(TM), and MicroStation V5 for the Power Macintosh(TM) platform. The company also announced Objective MicroStation(TM) an object-based expanded architecture for all MicroStation products, and its "Open Space" initiative. The latter is a strategy under which Bentley partners with one important developer in each of several fields to provide industry-specific development tools for third parties in those fields.

Programmer driven. That's a lot of product introduction in one quarter, but then again, it's a company founded and run by programmers. Technical continuity is important in code development of long-lived software such as CAD, says Greg, "and few companies can boast that their founders wrote the original code and are still in charge of technical development several product generations later."

Keith, Barry, and Ray lead the 75-member code-development team. "They set the example for hard work," says Gary Cochrane, product manager for MicroStation Modeler.

It may be that they are just following the example they had at home growing up. Tom Bentley, their recently deceased father, was a mechanical engineer at DuPont who taught his sons to develop inventive skills and to be civic-minded. Their mother, Bonnie, a former school teacher, passed along to them her love of learning and a bookishness that Greg says spawned their inclination toward programming.

But, they're not all work and no play. Four of the brothers are regulars in the company's bowling league, and, says Cochrane, they encourage the blue-jean-bedecked employees to include some unwinding time in their hectic work days.

"When we were all working long hours finalizing MicroStation V5," recalls Cochrane, "Keith sent around a note saying he had $200 in his desk drawer and that anyone working late could just take money from the pile and go get a burger if they needed to."

It's all in the family.