Relationships are at the core of the most important things we do, not only as leaders but also as humans.

Relationships are how we form partnerships and families and organizations and communities.

All relationships--personal and professional--experience ups and downs. There are great times when you can almost read each other's minds, followed by challenging periods when you seem to be miles apart. These variations happen even in healthy relationships too. But if things seem to be more down than up when you look at an important relationship in your life--whether it's a colleague or a friend, a key employee or a business partner--you may start to wonder if something more serious is going on.

Here are some symptoms that should cause you concern, together with the preventive measures that can help you keep your relationships healthy:

1. Resentment. Resentment grows when someone feels unheard or dismissed. Left unchecked, it leads to bitterness and a smoldering anger that scorches everything around it. Communication goes from difficult to impossible and negativity is overwhelming. The best prevention is a combination of equity and communication. Make sure everything, from cash to household or office responsibilities, is handled fairly, and if there's something on your mind or you're feeling frustrated by a situation, talk about it.

2. Disrespect. Mutual respect is a cornerstone of all successful relationships. If you're sensing disrespect, whether you're giving it or receiving, you have a fundamental problem. It's sometimes a case of never having learned how to disagree respectfully, and at other times a more serious or personal issue.

3. Dishonesty. An occasional lie is forgivable--and, depending on your moral outlook and the situation, sometimes even appropriate--but lies about serious matters, or a daily barrage of deception, are seriously harmful. Often a key to the source lies in asking yourselves what function the lies are playing. Is it to give an illusion of competence in some area, or to prop up a failing sense of self-respect? Once you understand why, you can find more positive ways to achieve the same end.

4. Mistrust. A single betrayal--or an act perceived as a betrayal--can wipe out a lifetime of trust. If trust is absent, again, ask why? Is it warranted, or is it coming from something unresolved in in a past relationship? If there has been a breach, is it too serious to be mended?

5. Distancing. If one or both partners is consistently tuning out, seeking distractions, and making a conscious effort to avoid making a connection, it may be that the bond between you has already been severed. People check out for all kinds of reasons--some temporary, others permanent.

6. Defensiveness. It's not unusual to respond defensively when you're challenged. Over time, defensiveness shifts into the "whatever" stage, which throws up a protective isolating barrier. Wherever the need for this protective stance originates, it prevents open communication and a meaningful relationship.

7. Contempt. The most serious possible sign; once a relationship is at this point, the odds of survival are low. It's often a way of turning one's own despised and unwanted feelings outward, so left alone it may recur in later relationships as well.

Think about the relationships that are important in your life and work, and ask yourself if they have any of these qualities. If so, you need to take action. It may mean a new focus on growing together in healthier ways, or more structured communication, or a change in the ground rules. You may need the assistance of a counselor to make things right--and you may end up needing to walk away. But with the right intervention and a commitment to success from both parties, you can end up with a newly strengthened partnership.