Fifteen years ago, I didn’t believe I had the financial resources to go to college. Instead, I spent my time thinking about a future where I took a few classes at a local community college and worked at a local factory.

Ten years ago, I was a college student. I was working towards a degree in computer science and had dreams of working at Microsoft.

Seven years ago, I was working in a genetics research lab. I was single, living in an apartment, didn’t own a vehicle, and couldn’t imagine being married.

Five years ago, I was working for a nonprofit organization. I was married, living in a different apartment in a different city, and couldn’t imagine having a child. I also couldn’t imagine being debt free.

Three years ago, I had a child. I was also near debt freedom. I was spending most of my spare time writing, but I couldn’t imagine a situation where I would be able to make a full time career out of it. I also couldn’t imagine being able to manage more than one child or live anywhere other than the little apartment we were living in.

Eighteen months ago, I had become a full time writer. I had a second child. We had moved into a house. At that point, I couldn’t imagine writing a book, editing it appropriately, and getting it published – it seemed like an unimaginably huge endeavor. I also couldn’t conceive that we would have a third child, as two seemed to keep our hands full.

Today, I have a book already in print, a second book that’s finished and due out in a few months, and a third child due in just a couple of months.

What can’t I imagine happening next?

Here’s the truth: an awful lot of lives go through the same progression as my own. Not in the sense of the specific things that change, but in that the specifics of their life change so drastically in even a few years. And we don’t see it coming, either.

At each of those times above, I thought my future would go on more or less the same way that it was going right then. I was repeatedly wrong.

The best thing you can do with your money and with your skills is prepare for change. Why? Because things will change.

You’ll lose a job. You’ll change careers. You’ll find a partner. You’ll have a child. You’ll move to another state. You’ll find a new passion. You’ll get sick. You’ll get well. People will leave your life. People will enter your life.

Things will change.

It’s this simple fact of life that leads me towards believing that the best personal finance tool that people can have is a big, fat emergency fund.

With a nice, healthy cash reserve in hand, a person can roll through these changes with ease. A job loss doesn’t mean an apocalyptic disaster in your life. A choice to try a new career becomes exciting and fun instead of scary. Falling in love and moving across the country becomes a whirlwind adventure instead of an exercise in tightrope walking. Opportunities spring up and you can take advantage of them instead of having to run away in fear.

Never, ever let debts and a lack of money on hand keep you from jumping on board with your dreams when the chance comes along. You have the power, right now, to get things under control, eliminate that debt, pick up some new skills, and be ready for the inevitable changes that will come your way.

When that chance comes, you’ll be ready.