Dion and Robert Algeri have spent their lives selling together. Partners in Great Jakes Web & Print Design, the brothers started their cooperative business ventures when they were kids as they shovelled driveways, set up a lemonade stand and sold toys they'd outgrown to the moms of neighbourhood children. In college, they developed a banner-making kit for promoting campus events and ran the operation out of their parents' garage. Next was an Internet entertainment company, Shortbuzz, which they sold to CMGI Inc. "After that success, it only seemed natural that we'd work together again," says Dion, who launched the New York-based Great Jakes with Robert in 2001.

Two sisters came up with an innovative pet-treat concept when they started the Lebanon, N.J.-based Chomp Inc. in 1999. Sarah Speare and her sister Lesley Lutyens are pioneers in the pet-candy market with such items as Yip Yaps, a bone-shaped breath mint for pooches. Both sisters were at career transitions -- Sarah burned out as an executive director at a non-profit, and Lesley was seeking a new direction after starting a children's knitwear business. The sisters pooled their artistic talents, "networked like crazy," according to Lesley, and took business classes to further their research. With a $25,000 loan from their mother, they left their jobs and set down the path of catering to canines.

Sibling partnerships have their own set of benefits and drawbacks. "The relationship possesses all the strengths siblings enjoy: trust, familiarity, shorthand communication and shared values," says Thomas Davidow, president of Genus Resources LLC, family-controlled enterprise consultants in Needham, Mass. These factors can be powerful and can create "a competitive edge in the marketplace," says Mr. Davidow. A major drawback of sibling partnerships is obvious: Those that go wrong can put both business success and family relationships on the line.

For Chomp and Great Jakes, partnership is a natural for business and personal objectives. The entrepreneurs explained the benefits and disadvantages to working with each other:

Trust

Both sibling teams named trust as a primary reason they partnered. "When you're running a business, you have to know your partner puts the success of the business above his own personal gain -- this doesn't always happen," says Dion. In working with Robert, "the trust is implicit, which is a great comfort," he says.

Sarah believes that having a partner you can trust helps advance the business quickly. "Being sisters, there is so much trust, you can push further with confidence [and] go right for the top," she says.

Complimentary Skills

Because of their family roles, siblings often bring different and complementary skills to the business. Lesley, for example, is a manager of details. Her behind-the-scenes work made her the choice for the job of vice president of product development. Sarah, on the other hand, is more of a big-picture thinker, the dreamer who serves as the company's vice president of marketing. "Sarah's the visionary, it's my job to rein it all in, to ask 'How much will this cost?' " says Lesley.

At Great Jakes, Robert brings his experience as a feature-film producer, and Dion adds his graphic-design and Web-development expertise. "Our experiences allowed us to bring different and complementary skills to the table," says Robert. Streamlined Communications "We understand each other on a level that's beyond what most partnerships can hope for," says Robert. A glance between brothers, according to Robert, imparts more than a "paragraph of instruction," would with other partners.

This heightened communication helps the duo complete work faster because there's less need for explanation. They have communication problems occasionally, says Dion, but "these are trivial compared to communication issues I've had with previous business partners."

Such streamlined communications helps get work done. "We know each other so intimately, we can be efficient and cut right to the chase -- no office politics," says Lesley. The lack of hierarchy within Chomp's ranks allows it to move quickly. "Everyone clearly understands their roles," says Lesley, adding that there's a "strong bond that comes from the energy of building an exciting business together."

Of course, no duo can work together without facing difficulties. Mr. Davidow warns that when siblings have disagreements, they can "grow to mammoth proportions because of underlying issues that may exist." He adds that sibling rivalry shows up in power struggles. "The power that binds is also the power that disrupts."

Robert and Dion say they worked out any rivalries they once had long ago. Still, Robert concedes they sometimes disagree on marketing issues, such as decisions about Web-site text or the look of the logo. "The biggest difference of opinion happens in areas where our skills overlap," he says. Familiarity Breeds Contempt "Extreme comfort," is how

Lesley describes communications with her sister, Sarah, but sometimes there's a bit too much comfort. "Sometimes we're too familiar and need to remember to treat each other as we would another professional," says Lesley. "My sister puts up with a lot from me. Sarah has the patience of a saint." Lesley works from an office in Cambridge, Mass., and Sarah from Falmouth, Maine. The distance can be a "relationship saver" at times, Lesley says.

While the sisters agree on the strategic direction of Chomp, their views of the world can cause strife. For example, when Lesley questions why sales aren't better with a current customer, Sarah wants to give the customer the benefit of the doubt. Further, if sales are disappointing, Lesley wants to understand what Chomp or the customer is doing wrong, while Sarah considers how the new sales racks are helping the company increase press coverage and sales. "Lesley tends to focus on where things aren't working, and I tend to focus on opportunities for growth and increased exposure," says Sarah.

The Algeri brothers spend as many as six days each week together and frequently seven when there's a family event on a Sunday. "As much as I like my brother, I do my best to avoid him on Sundays," says Dion. Robert agrees that it's crucial to separate his work duties from personal duties. "When Dion's friends have asked me to go out, I've politely declined."

Thomas Starko, partner in DoudHausnerVistar, a family-business adviser in Glendale, Calif., offers three tips on making a sibling business partnership effective:

Shared vision

It's critical to have a shared vision of what individuals want to achieve together. That begins with a personal vision -- each sibling must be clear about what the future for themselves and their families looks like and believe that a sibling partnership is the best way to get there. Due to a feeling of duty to others in the family, family members may feel trapped or that their options are few. All family-business shareholders want three things: business prosperity, family harmony and personal well-being. A shared vision allows the partners to balance the goals of all three.

Strategy to reach your goals

A family business is still a business, and too few take the time to plan. It's like shooting a movie without a script; you're going to end up spending a lot of money on a flawed product and frustrate a lot of people. The success of many family businesses sits perilously on the knowledge that's inside the founders' heads. Getting your core competencies down on paper and establishing systems, processes and structures goes a long way to ensuring sustainability of the firm.

Establish effective communications and resolve conflicts

Good communication practices don't come easily, but they can help or hurt a sibling relationship. It's not just establishing strong communications between family members, but creating a culture in which effective communications become an everyday practice. Most conflicts are the result of differing expectations or a lack of communication. Messages are easily mixed -- and when you have family and business messages together, the chances are even higher for miscommunications.

Written by Kimberly L. McCall

Ms. McCall is the president of McCall Media & Marketing Inc., a business-communications firm in Freeport, Maine.