Most U.S. companies employ workers on an at-will basis, which means that they can let their employees go at any time and for any reason, provided it's not discriminatory in nature. As such, it can be hard to feel secure in any given role, even if you've been with your employer for quite some time and have a good reputation to boot.

The good news, however, is that there are steps you can take to lower your chances of losing your job. Here are four to focus on in the coming year.

1. Know one key thing about the company that no one else does

It's hard to fire the one person in a company of 300 who knows how to reboot the tricky routers or navigate bugs in the reporting system. If you really want to buy yourself some job security, take a deep dive into something important that's specific to your company and become the go-to source on it.

Along these lines, if there are clients your company depends on for much of its business, aim to start managing some of those accounts. If you develop relationships that help keep those clients on board, your employer might worry that losing you will mean losing business. Once that reality sets in, you're less likely to get the boot.

Smiling man in business suit at laptop.

IMAGE SOURCE: GETTY IMAGES.

2. Be visible

Your employer may not think twice about firing the number cruncher in the corner who's one of several folks on the accounting team. But a person who works in many areas of the business is a different story.

If you're looking for some peace of mind on the employment front, put yourself out there so your name starts popping up all over the place. Volunteer to help another team with a high-profile project or initiate one of your own with wide impact. Doing so will not only make you more valuable, but remind your company's higher-ups that you're a key player.

3. Keep growing professionally

It's easy to grow complacent on the job, but doing so can sometimes send the message that you're not all that motivated or interested in helping your company succeed. A better bet? Boost your skills in the coming year so that your manager can't help but notice your effort.

You can sign up for online courses, pursue a professional certification, or even spend more time researching industry trends. The key is to show your boss that you're constantly evolving, because once again, that makes you instantly valuable.

4. Build more companywide relationships

When we think of networking, it's often in the context of meeting people from various companies within a given industry. But networking within your company is just as important, especially if you're eager to lock in some job security.

The more people who think highly of you at your company, the less likely you are to be deemed dispensable, so make a point of developing relationships with other managers and teams -- even those you don't work with on a regular basis. Not only will it help your reputation, but it might allow you to avoid a job-loss situation if, say, your boss is forced to eliminate your position but there's a role elsewhere that another manager is willing to give you.

Unfortunately, you never know when you might lose your job through no fault of your own. But if you want to lower the chances of that happening, focus on these key steps. With any luck, they'll buy you a little peace of mind and may help avoid an extended stint of employment.

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