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For many Americans struggling with managing their debt, the simple act of picking up the phone can be terrifying. Why? Debt collectors.

In the aftermath of the Great Recession, the debt collection industry has seen a boom. And as more and more collection agencies have been entering the market, complaints about collectors' abusive practices have reached all-time highs. The Wall Street Journal reported that the Federal Trade Commission saw a record-high number of consumer complaints about debt collectors in 2011: 164,361.

That rise in complaints doesn't necessarily mean collectors are getting meaner or breaking more laws. And, according to the four debt collectors we spoke to, the collection businesses they worked for followed the standards and laws set out in the Fair Debt Collection Practices Act, the legislation that tells collectors when and how they can contact you.

We've heard stories of overseas debt collector scams, debt collectors going after grieving parents for their son's debt and debt collectors calling people who don't even have debts. But we rarely hear stories about what it's like to actually be a debt collector.

So we spoke with four people about their experiences as debt collectors and what consumers should know when they get on the phone with them.

Death threats are part of the job

If there was one universal among all four debt collectors we spoke with, it was that death threats happen.

"One time someone mailed us human excrement in a box," said Kerri Fivecoat, a freelance journalist who worked in the debt collection industry for more than a decade. "It happened at the internal third-party agency I worked at. We always had lots of bomb scares."

Being a debt collector can be a scary experience, says Ben Nettleton, who used to work in a third-party collection agency in the Houston area. While his stint as a debt collector lasted only 89 days, he was left a very threatening voice mail one night by a man who called himself a "straight shooter."

"I got this and I'm not someone who's offended easily, but it did make me think," Nettleton said. "Does it throw you and kind of shake you? Yeah. I didn't call him back."

Death threats, combined with the emotional appeals from the people they call, make debt collection a tough career path. Bryan Franzoi, who is currently working as operations manager at Cumulus Funding and has spent more than 15 years in debt collections, said the housing market crash of 2008 and 2009 was especially tough.

"You're a human being, you're going to be affected by it. There have been times where it has been very upsetting to me," he said. When Franzoi was working as a manager of debt collectors, he even had an employee break down and start crying.

Michelle Dunn, a debt collector and author of "Dealing With Aggressive Debt Collectors: What to Do and How to Do It by an Industry Insider," says it's hard not to take consumers' threats personally, but the key is trying to understand the position the debtors are in.

"When somebody's in debt and they have bill collectors calling them, that's not their only problem. They normally have something else going on," Dunn says. "The last thing you need is a bill collector calling you. They may lash out on you. I've had people tell me they were going to find where my children went to school."

Not all debt collectors are mean

Imagine going to a party and telling someone that you're a debt collector. It's not exactly the most popular career path.

"People cringe when you tell them what you do," Dunn says. "A lot of times you don't want to tell them what you do. They're only dealing with debt collectors when they're in a bad situation."

While most of the debt collectors Fivecoat worked with would try to take a calm and compassionate approach with debtors, there were a few bad eggs.

"There are people (who enjoy debt collection)," she says. "They would really get into what they were doing, and they didn't have the personality to start out with people being nice. Sometimes it was effective when they were being more forceful or more assertive."

Even though he has worked with some bad collectors, Franzoi said the stigma about debt collectors is just incorrect.

"Ninety-nine times out of 100, that's a totally wrong misconception, and they're really trying to put them in a better financial situation," he said.

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