Asset disposition. Reverse logistics. Whatever you call it, getting rid of your old computers is more complicated than you might think.

The hardest thing to do with a computer isn't buying it or setting it up or using it or fixing it. The hardest thing is throwing it away.

To dispose of just one PC without exposing sensitive personal or corporate data, without running afoul of environmental regulations and without wasting what can be reused requires planning and time and, yes, money.

And that's just one PC. According to the International Association of Electronics Recyclers, about 100 million pieces of computer equipment a year are being added to the massive heap of what's called "e-waste". By 2010 that heap will contain 1 billion units of computer equipment.

Out of all that junk, only 40 million CPUs, monitors and printers annually are properly "demanufactured" to safely dispose of the hazardous waste encased inside and to recycle the reusable materials.

Every computer contains more than 30 elements, many of them highly toxic. Deconstructing them is the disposition business. And it's booming. The business of throwing away computers is growing faster than the market for buying them.

CIOs, it's time to create a plan for safely disposing of your computers. Most companies don't have this kind of plan. Heck, most companies don't even know where their old computers are. Recyclers talk about discovering thousands of machines that no one knew even existed, piled up in closets. Out of sight, out of mind.

Maybe junking those old Pentium IIs is something you've been meaning to get around to. Maybe it's on your to-do list but way down. You have, what, hundreds of computers to get rid of? Thousands? What to do?

Step 1: Find Them. Decide What to Do with Them.

Your choices: Redeploy, sell, donate, chop up for parts, chop up for recycling

Before you get rid of a computer, you have to find it. Stampp Corbin, CEO of information technology disposition company RetroBox, recalls one company that had 9000 employees on its books but 23,000 computers, many of which were dead and stacked in hallways, closets, attics and basements. That translates to about 2.5 PCs per employee. "Typically, thousands of machines come out they didn't even know they had," Corbin says.

After you find your machines, you need to sort them by their likely fate - redeployment, resale, donation, chopped up for parts or chopped up for recycling.

Situations vary, and as computers surface the CIO and the disposition company should build a reverse logistics plan. Bold CIOs will create a repeatable disposition process, an end-of-life asset management plan as comprehensive as their asset deployment plan.

Step 2: Get Rid of the Data.

Your choices: Do it yourself or get someone to do it for you; save or destroy the hard drive

Hard drives must be wiped. This is not optional. The risk of not wiping drives - the potential liability if sensitive information gets out - easily justifies the cost of doing it. Two years ago, the state of Kentucky got rid of computers that still contained confidential files naming people who had AIDS and other STDs. In May, the state of Montana disposed of hard drives that still had Social Security numbers and medical records on them. Then there are the risks of losing computers in transit or even of competitors trying to get their hands on them.

Data wipes come in several flavours, each with pros and cons.

First, decide if you'll sanitize the drives at your site or if you'll ship them off to the cleaning company's site. Bringing the cleaners to your site is more secure - and pricier. If you send the computers out, put a BIOS password on their systems to prevent access to their drives.