Denver's mayor believes his city can save more than $50 million a year by helping those on the street.

Providing the homeless (search) with jobs and housing, while offering voluntary programs for their addictions and mental illnesses, is part of a national model called "Housing First." It's a support program for homeless people that provides housing, substance abuse counseling, mental health and employment services.

"We can improve their life, we can improve our life, and we save three bucks for every one we spend," said Denver Mayor John Hickenlooper (search).

Two hundred cities across the country have implemented this plan and the federal Interagency Council on Homelessness says Denver's version is one of the most aggresive. The most successful is in Philadelphia; in just four years, it removed 75 percent of its homeless population from the streets.

But Bob Cote, a former homeless person who now runs a program for male addicts, "Step 13," is critical of the Housing First program.

"I've watched them have homes be all set up and the next thing you know, it's diabolical. They're out drunk again or shooting heroin," Cote said.

Cote, a recovered alcoholic, said Denver's plan lacks an appropriate emphasis on self-responsibilty.

"Some people will abuse it. They're system abusers. They're system dependent. And they'll say, 'Oh, I got a free pad.'"

Hickenlooper's goal is to have 70 percent under a roof in five years, but he knows he can't reach it without the endorsement of the people he's trying to help.

"I do believe once you get to them and show them what it's like not to be sleeping under that bridge that they will be suddenly more receptive to counseling and programs," he said.

Click in the box above to watch a report by FOX News' Carol McKinley.