The Mayo Clinic describes a narcissist as someone with “an inflated sense of their own importance and a deep need for admiration.” When you run a business with a narcissist, you might find yourself constantly stroking his ego, responding to his demands for attention or battling for recognition, especially if you want to preserve your professional relationship -- and your business.

Don’t Expect Too Much

If you want to maintain a harmonious working relationship with your narcissistic partner, you might need to lower your expectations. People with narcissistic personalities sometimes promise more than they can or intend to deliver, often using this method to achieve their own ends. Don’t depend on your partner for much moral or technical support, and don’t take it personally if he’s not there when you need him or if he puts himself first. Instead, focus on what you need to work toward your own goals, while ensuring you don’t fall victim to your associate’s selfish tendencies.

Acknowledge Him

A narcissist needs to be the center of attention at all times and will take it as the ultimate insult if you don’t immediately jump when he calls. If you don’t want to engage in a power struggle with your partner, you might need to be willing to cater to his needs and demands -- within reason. If you don’t feel comfortable offering an over-the-top confirmation of his inflated sense of self, executive coach and management consultant Steven Berglas recommends in “Forbes" magazine that you respond with a neutral but still affirming statement such as, “Sounds good to me.”

Don’t Criticize or Blame

People with narcissistic tendencies frequently appear conceited, but their outward arrogance often masks a deep need for constant validation and admiration. Well-intentioned, constructive criticism can humiliate a narcissist and prompt him to lash out. Even if you’re in the right he might take offense. If you need your partner to change his ways or come around to your way of thinking, present it as though you’re asking for his help. Give him the admiration he so deeply craves and you’ll give him incentive to collaborate with you.

Help Him

Narcissists are essentially looking for people who can make them look good or help them achieve their goals. If you support your partner in these aims, you might be able to avoid conflict and competition. As long as the arrangement benefits him, he’ll be more interested in preserving it. Don’t slack off on your work or set aside your interests, however, because your partner likely won’t bail you out if you get into trouble. Instead, look for small ways to keep the peace and keep your partner in line.