Harvard Business Review:

We’re all too busy. And we can’t stand people who distract us at work and derail our productivity. There may be no escape from other people, but you can take steps to regain control of your time and schedule.

• State your preferred method of communication. Limit aggravation by proactively informing colleagues about the best way to reach you, whether it’s via phone call, text, email, or tweet.
• Require an agenda for meetings. Vague or rambling meetings eat up too much of our time. Insist on seeing an agenda before you commit to attending meetings so that you can contribute fully. Model the practice by creating an agenda for any meetings you chair and offering to share the template with others.
• Make others prepare. Before you commit to a meeting, ask if people have done their research and if the real decision-makers will be present.

Adapted from “Stop People from Wasting Your Time” by Dorie Clark.