Aristotle viewed friendship as ranking among the highest virtues. It was an essential element in a full, virtuous and worthwhile life. For Aristotle, there were three kinds of friendship:

1. Friendship of pleasure: Two people are wonderfully happy in each other's company.

2. Friendship of utility: Two people assist each other in everyday aspects of life.

3. Friendship of virtue: Two people mutually admire each other and will be on best behavior in order not to jeopardize their relationship.

The value of friendships is perhaps most emphasized throughout the holidays. We share special gifts, look for opportunities to connect, and vow to do a better job of keeping in touch. That's so much easier said than done, given the busy nature of life.

I can't imagine what my life would have been like if I hadn't had such loyal and true friends. I am fortunate to number among them several classmates from first grade, as well as people I just met. My friends have saved my bacon over and over again. A few have actually saved my life.

So where does friendship fit into your business life? That's what often begins as "friendship of utility."

You probably spend most of your waking hours at work, so friendships are natural. Working together can easily turn co-workers into best friends, making jobs more enjoyable and the workplace a home away from home instead of a pit of boredom or an arena of stress.

But friendships need to be managed appropriately, just like every other workplace relationship. You need to understand and respect each other's boundaries and privacy, just as with personal relationships. But work issues can present some unique challenges when ensuring that both your job and the friendship are not at risk.

- Limit social chatter. Don't let your friendly conversations overshadow your responsibilities. Stay focused on your job most of the time.

- Keep private issues private. When you have problems to discuss, do it over lunch or after work. You don't want to make your co-workers privy to your personal dramas - and they probably don't want to listen to them either.

- Avoid gossip. Most of us love to talk about other people, but keep your natural inclination to share rumors about co-workers or managers in check. If colleagues realize you're gossiping about them, the backlash could be unpleasant.

- Don't do each other's jobs. Pitching in to help a friend in a crunch is admirable, but keep to a reasonable limit. Your manager is in charge of assignments and responsibilities, not you. You don't want to spend so much time helping a friend do his or her job that you neglect your own.

- Include, don't exclude. Don't ignore the rest of your workplace. Invite other co-workers to lunch, and include them in your conversations so they don't feel left out. You may even make new friends by expanding your circle at work.

If you value your relationships with family and friends outside of work, you need to work to maintain them. Take a few cues from your job for evaluating your priorities and scheduling your activities. These "friendships of pleasure" are worth all the effort you put into them.

A mission statement might be helpful. You have career goals and aspirations. It's just as important to establish what kind of relationship you want with your family and friends. A clear mission statement can help keep you focused on your personal life goals, especially when your schedule gets demanding.

Time management is just as important for friendships as for your business schedule. Keep all your commitments with family and friends on one calendar, planner or smartphone so nothing falls through the cracks.

Spend some time planning your personal hours. Review your schedule so that you are prepared for your most important activities.

Honor your plans. When you must choose between events, decide which is more in line with your mission, values and goals.

Mackay's Moral: The best vitamin for developing friends is B1.

Harvey Mackay is the author of the New York Times best-seller "Swim With the Sharks Without Being Eaten Alive." He can be reached through his website, www.harveymackay.com, by emailing [email protected] or by writing him at MackayMitchell Envelope Co., 2100 Elm St. SE, Minneapolis, MN 55414.