I recently had a conversation with a young woman whom I mentor who was very disappointed in a colleague’s behavior. The two, in my mentee’s words, “enjoy a good relationship and are friendly toward one another.â€ The two were also recently working jointly on a project. My mentee was coordinating with an outside vendor and the colleague was managing the project with a senior level executive internally. Apparently both had casually agreed on their roles as the ground work was being done. When it came time to execute the project, the colleague called the outside vendor (my mentee’s contact) secured the deal and then promptly wrapped up the assignment with the senior level executive. Her reasoning: It was late (6:30pm on a Monday) and my mentee had already left for the day. The colleague didn’t want to disturb her evening. I’m not a sports person, but I believe that’s what they call an intercepted play — or as my mentee saw it, a foul.

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My mentee was angry for a number of reasons: At her company there are no off hours. Everyone has a BlackBerry and so even if you don’t want to disturb someone with a phone call, texting and e-mail are always appropriate for matters concerning urgent business or communication etiquette.

The other breach was in their perceived friendship. But I firmly reminded my mentee that there are no friends at work! Sure, there are folks with whom you go to lunch, share jokes, and exchange birthday and holiday greetings. There may even be colleagues with whom you share family information (children’s graduations, parent anniversaries, etc.) You may have even invited them to your wedding. But as Renetta McCann, former CEO of advertising giant Starcom MediaVest, reminded me in an interview, in a competitive work environment “a friend today is a foe tomorrow.â€ The goal for most individuals at work is advancement. How do you achieve that? It’s increasing your visibility, gaining the right exposure and being noticed by the right players inside and outside of your organization. Of course, there are perfectly legitimate and integrity-based strategies for achieving those goals. But for some, it’s accomplished by any means necessary.

Some of these people are quite obvious in behavior. Others you discover in your interaction with them. Will they disappoint you? Certainly! Should you be surprised? Never! Does this mean you should be guarded and paranoid in your place of work? Not at all. You should, however, be clear and deliberate about all your actions and interactions at work. As for my mentee’s colleague — now she knows how her colleague operates. One of my favorite quotes from Maya Angelou is, “When people reveal themselves, believe them.â€ Here are some guidelines for managing relationships on the job:

You may love your job and all the people you work with, but at the end of the day you are in a business environment where the goals of the organization are driven by business decisions.

It is absolutely necessary to build and develop relationships at work. This is not a social exercise. There will be people that you genuinely enjoy and like and colleagues with whom you will develop genuine friendships–that will happen effortlessly. But the goal of building workplace relationships is to accomplish your professional and business goals. Even if you don’t feel this way, know that your colleagues do.

Clearly outline goals and objectives in writing. Instead of verbal discussions, document through e-mails.

Stop getting emotional. If someone has disappointed you, take it as a gift. Now you know how they think and how they operate. Your job now is to be smarter about how you interact with them.

Always act with integrity — even if you feel others with whom you have a relationship don’t.

Sonia Alleyne is an editorial director at Black Enterprise magazine.