As a seasoned professional, you’ve probably experienced a company, a boss, or a customer who once drove you crazy. While the issue may have posed a big challenge in your career, the good news is that it’s in your past. You’re now in a different situation, where you can fully grasp this truth: Nothing lasts forever. Still, do you find it hard to stop dwelling in the past? It’s a common issue, yet effective leaders consistently avoid talking about what’s negative about their past. Instead, they habitually focus on what’s present, positive, and within their control. Rather than brood over yesterday’s woes, they talk about lessons learned and take those lessons to heart through appropriate corrective actions. This habit reflects a confident leadership style that’s more concerned with what’s going on today versus what happened in the past. It’s also a discipline that can help transform you from just any leader into a really great one. So, resist the temptation to carry on about prior negative experiences, particularly with colleagues and coworkers. Spend your time and energy focusing on the present and what’s productive, leaving any digging up of the past to those who do it best—archeologists!

Keep on the lookout for any tendencies to share negative past experiences about your:

Companies. If you’re seeking a new job opportunity, know this: It’s a cardinal sin to talk negatively about wherever you’re currently working. However, people do this all the time, not realizing that it makes them look like they have no filter or raises a red flag, signaling they might have a problem getting along with and/or badmouthing others. Regardless of whether you’re interviewing for a new position or commiserating about your former company with a co-worker in your new situation, always take the higher ground. Manage your talk to focus on how the new situation provides a better opportunity in terms of your professional growth and goals.

Bosses. It never pays to bash a boss, even when they’re no longer in charge of you. Why? First, if you maintain face and learn to control what you say despite your frustrations, you’ll portray yourself as a more positive, effective communicator and leader. Second, if you continue badmouthing a prior boss, this active verbalization keeps the issue alive, perpetuating needlessly inflicted self-pain and wasted emotion, energy and other such resources. In essence, you’re still allowing this person to control you despite the fact that he/she has no authority over you. So once you’ve moved on from a bad boss—or that boss has conveniently moved on for you—be strong and avoid the tendency to vent to everyone about how you felt, what you’re still feeling, what he or she did to you, etc. Let the past go to regain control!

Customers. If you dwell on past negative customer experiences, it may affect future customer relationships. Keep a tight lid on talking about customers who’ve bugged or offended you. After all, no customer is perfect and dealing with the occasional trouble customer is simply a part of business—a fact every professional manager must accept. Learn from your experiences and then move on, always capitalizing on the gift of these lessons learned and taking prudent corrective actions to ensure greater success rates with customers you’re serving today.

What else can you do to prevent badmouthing a former company, boss, or customer?