Are you the person you want to be? Even top leaders—world famous CEOs—struggle to pull off behavioral changes they aspire to.

For example:

Do you want to spend more time with your family—and promise to do so—only to find yourself regularly working late?
Do you want to be a calm, grounded person but find yourself constantly losing your temper with co-workers?
Have you vowed to stop micromanaging but then make excuses for yourself like “at least I’m better than George”?
Is there a habit you’d like to develop, like exercise, healthy eating, reading regularly but you never manage to get it off the ground?

Marshall Goldsmith’s latest book, Triggers, takes on this topic based on his extensive experience coaching top leaders.

Here’s a summary of the key points so far: Change is hard even when we want to change. We all have lots of excuses and rationalizations to avoid changing. One of our biggest blind spots is how powerfully the environment affects our behavior.

This past Sunday I had a firsthand experience of that third point.

I’d just arrived home from yoga. It had been an inspiring class and I was feeling relaxed and serene. Basking in the afterglow.

Inside the house, I found at least a dozen windows wide open. A strong breeze was whipping through the house. Outside, rain was threatening. Virtually all our ceiling fans were whirring and there were three—yes, three—radios tuned to NPR in various rooms.

Abruptly, my serenity vanished. Struggling to close a window, the wooden pull of the shade snapped sharply into the sensitive flesh on the underside of my arm. I yelped in pain and (mostly) surprise then burst into tears, unaccountably upset by everything and nothing. Where had my deep feelings of serenity gone? Couldn’t I withstand a little pinch and some swirling wind?

Thirty minutes later, still upset, I had no clue what had happened.

It’s the environment, stupid.

Goldsmith writes: “Most of us go through life unaware of how our environment shapes our behavior.”

Although I’ve written about how one distracted person can “infect” others nearby and also written about how over-stimulating environments can cause over-stimulated people, I hadn’t realized how powerfully the environment can affect whether we behave as the people we want to be. In the space of a few minutes, I had gone from a serene yogini to a sobbing mess.

Goldsmith goes on: “If we do not create and control our environment, our environment creates and controls us. And the result turns us into someone we do not recognize.”

I certainly had that experience on Sunday. And I don’t think I would have recognized the cause if I hadn’t been reading his book. I would have blamed my husband, my lack of self-control, the dream I had that morning, or any number of other factors. Once I recognized that the environment had affected me, I was able to take simple actions, like closing a few windows, turning off fans and shutting off two of the radios.

The big takeaway from reading this book so far: Self-control and willpower only go so far. You need to understand what environmental conditions are helping or hurting your chances of being the person you want to be.

Here’s a quote from Clement Stone in another great book on change, Influencer:

“You are a product of your environment. So choose the environment that will best develop you toward your objective. Analyze your life in terms of its environment. Are the things around you helping you toward success—or are they holding you back?”

Next time you want to make any kind of behavior change, make sure to get the environment on your side.