A teammate asked you for a favor last week and, of course, you said yes.

And now you’re stuck. You can’t back out of it without looking like a jerk. You can’t whine about it because you were the one who said yes. And you’ll never get back the Saturday you’ll have to forfeit for a task you really didn’t want to do.

Obviously, you need “The Power of Saying No” by Vanessa Patrick, Ph.D., before this happens again.

So why did you say “yes” in the first place if you didn’t want to do this thing?

We humans, Patrick says, instinctively want to belong and be liked, and being agreeable is often one way to achieve that. We tend to “think in people terms” most of the time, and saying no is a “harmony-buster.” We want to maintain a relationship with the person who asked for the favor. We don’t know how to say no and still keep our position in a group.

The easiest – and probably most frustrating – thing to do, then, is to acquiesce, even though Patrick says that very little personal good comes from doing a task you really, really don’t want to do. So what do you do?

Though it might feel as though the “spotlight” is on you, there are ways of managing that. Be prepared by knowing your values and your worth, postpone or deflect your decision, postpone your participation for another time or simply “resist the pressure.”

Learn the “art” of an “empowered refusal” by using a mere two words to state your position. Never say you “can’t,” and erase “submissive filler” words from your vocabulary. Learn to assess the benefits of saying yes to yourself and to others and remember that you shouldn’t say no all the time.

Institute a few “personal policies” that are essential to you. Have boundaries. And lastly, always take care to present the right body language, personal style and gestures. Your nonverbal communication can say a lot and that might quickly undo a “no.”

You had very little problem saying “NO” when you were a toddler. If it felt good then, it can feel good again with “The Power of Saying No” in your hands.

The word seems so simple, just a few movements of the mouth, but the author explains why saying “no” isn’t easy for most humans. Readers learning about themselves in those chapters may squirm because what’s discovered is a sometimes-uncomfortable part of an uncovery – you must know yourself, Patrick suggests, before you can see how to use “’standing-up’ words” to hold your ground.

For readers who shudder at confrontation, this may seem impossible, but fear not. Patrick offers help by patiently underscoring her ideas, through step-by-step exercises, and with analogies that are universal and thus easily understood.

This is a book that the timid will want to read twice and keep handy. It’s one that abrupt-minded readers will want to consult when situations get dicey. “The Power of Saying No” is a book you’ll both favor.

Terri Schlichenmeyer’s reviews of business books are read in more than 260 publications in the U.S. and Canada.