The Washington run-in: A behavior guide

Her overarching suggestion: Proceed with caution.

“Many people work very hard to separate their personal life from their professional life and they treasure their privacy, while others live life like an open book,” she wrote in an e-mail. “Don’t assume that everyone wants to maintain the same relationship with you outside the office that they have with you at work.”

Mitchell said people in such a situation should use a “less-is-more” default setting. Keep the encounter short, avoid lingering eye contact and hold conversation to a minimum — until you detect a message from the other person that “more” is acceptable.

“After a simple ‘Hello,’ read the non-verbal signals that an individual sends to determine if a next step is appropriate,” she said.

These signals indicate the other person wants to keep the encounter short, she said: no questions or conversation beyond “hello”; no introduction of companions; no eye contact; closed body posture; or a telltale closing statement, like “Enjoy your evening.”

The alternative is that the colleague encourages more conversation, invites you to join his or her group or tells you to hop on the neighboring treadmill. At this point, Mitchell said, you should decide whether you want to continue the interaction. Does “more” feel right? Act according to how you answer that question, she said.

“At all times, you should use your powers of observation and your people skills to make these encounters less awkward for both sides,” she said. “Our manners are on duty 24/7. We don’t take them off when we remove a tie or stilettos at the end of the workday.”