Need to Regain Your Sanity? Learn to Say No.Don't feel like you have to take every opportunity that comes your way. But choose wisely.

Mary* was doing well as VP of business development at a San Franciscotechcompany. She'd been hired to create goodwill within the community, and she was a perfect fit. But her work had started suffering. Her CEO had asked her to take on a new project in Brazil, which would require her to spend at least a third of her time there. Her instinct was to say yes; she didn't want to lose her CEO's approval, and theopportunitywas an honor. But realistically, she couldn't be in South America and do what she'd been hired to do in San Francisco, too.

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When I met with her, I recognized the problem immediately. I've been an executive coach for more than 25 years, and Mary had made one of the biggest mistakes I see among top executives andfounders: They're always saying yes. Leaders want to grow business, please people, avoid conflict, and keep a job. But accepting every request or business proposition can render leaders overloaded and overworked. Since this prevents them from thinking clearly, it can also keep them from focusing on their -- and the organization's -- most important work.