Turning to open-source software for an enterprise resource planning system is a big challenge for most companies—so big they steer clear of it.

"No matter how bad their current system is, they feel like they can't afford to change," says Don Ladwig, senior business solutions architect at Idalica, a systems integrator in Oceanside, Calif. "But very often, they can't afford not to, either."

In the right business case, Ladwig says, companies can achieve significant savings through lower development and support costs by moving to open-source software.

Those typical business cases, he says, include first-time ERP adapters such as a midsize business looking to bring a variety of homegrown systems under one umbrella or a larger business looking to quickly integrate multiple systems inherited through new acquisitions.

Ladwig's firm works with Compiere of Portland, Ore., for its open-source applications because of growing interest among clients and Compiere's skill at integrating a company's existing systems.

Compiere is the brainchild of Jorg Janke, a former Oracle developer. He says his company supports and trains software consultants and companies that download, develop and, ultimately, perpetuate his product.

Despite its promise of cost savings, the main draw for an open-source enterprise package, Janke says, is vendor independence. "Most large enterprise systems are in production in some form for 10 to 15 years," he says, which increases their vulnerability in a marketplace that has seen its share of vendor consolidation and product support that has simply faded away.