As much as it goes against everything you’ve ever heard about the power of positive thinking, it’s not all good. Just because I study optimism does not mean I believe it is helpful to think positively all of the time. Research shows that fantasizing about your dreams coming true isn’t always helpful and can ultimately interfere with your ability to achieve your actual goals.

The problem with positive thinking is when it disconnects you from reality. If you have achieved your goals in your mind’s eye, studies show you are less likely to consider the concrete actions you need to take and the possible obstacles in the way. Psychologists refer to positive fantasies of virtual achievement as “mental attainment.” As we all know, mentally achieving a goal has nothing to do with actually achieving that goal. In other words, all the daydreaming in the world won’t help you land that job, meet your soul mate or get an A in physics.

Gabriele Oettingen, professor of psychology at New York University, has been researching the problem with positive thinking for years. She has done studies in a number of demographic groups, in different countries, and with participants who have a range of personal wishes, including health goals, academic and professional goals, and relationship goals. The outcome is the same:

Consistently, we found a correlation between positive fantasies and poor performance. The more that people ‘think positive’ and imagine themselves achieving their goals, the less they actually achieve.

People who positively fantasize about the future don’t, in fact, work as hard as those with more negative, questioning or factual thoughts, and this leaves them to struggle with poorer performance.

In the short term, a sunny outlook helps you feel good, but it’s short-lived. Also, if things don’t work out as planned and reality catches up with your dreams, disappointment, frustration and helplessness set in.

But it begs the question: if positive thinking doesn’t work, what does? Oettingen recommends a four-step exercise that combines positive fantasies with reality that can be applied in everyday situations. She calls it WOOP: Wish, Outcome, Obstacle, Plan. Here’s how:

1. Define the Wish

2. Identify and visualize the desired Outcome

3. Consider all the potential Obstacles in your path

4. Formulate a Plan to work towards and achieve the wish

According to Oettingen’s extensive research, WOOP has helped people find success in all sorts of pursuits including weight loss, business negotiations, in the classroom and in relationships.

So if you’re serious about your goals, stop daydreaming and WOOP it up.