David Hurley credits his wife with helping turn his business around. When he started an aviation services business in 1984, Johanna Hurley consciously vowed not to get involved, focusing instead on raising the couple's three children. But when the recession of the early '90s left the company with too few clients, not enough revenue, and an unwieldy business plan, Johanna stepped in.

Though an artist and writer by training, Johanna quickly spotted segments ripe for cutting costs. She suggested moving to smaller digs inside a hangar. Next, Johanna put her artistic and literary skills to work by creating a direct-mail campaign built around a high-quality newsletter.

Johanna says she had serious reservations at first. "I made a promise to myself that if our marriage started to be affected in a negative way, I would leave the business."

Instead, both insist that the partnership made their marriage stronger. The Hurleys, who grew their business to $25 million in revenue before selling to a large international corporation in 1998 (David stayed on as chief executive), found success by sharing an equal commitment to hard work and to saving the company, and by sticking to defined tasks. Employees are quick to notice when one member of a family team lags, Johanna says. "People have to be held accountable. People need to bring value, and hold their own weight."

At Burford Company Advertising, Doug Burford makes it clear that family perks start and end with hugs. "They're as dedicated as anyone. Nobody cuts them any slack. They make the same salaries that everyone else makes. You have to be very careful about that. You can't have favorites."

While there's no way to tell for sure in advance whether a family relationship will thrive or flounder in a business setting, Dr. Ralph Daniel, a California-based psychologist who specializes in family business, suggests that would-be family partners look at their personal history together.

"Each person should create a short list of all projects you've worked on together, whether it's planting a garden, building a porch, or buying a house. Annotate the list - rate it. How well do you work together? Then exchange the lists and discuss them," Daniel says. "These are the same kinds of issues that are going to come up [in business]. And they're going to become highly exaggerated and accentuated when money becomes involved."