Carnet de Passage

A Carnet de Passage is a customs document that identifies a vehicle - it's easy to think of it just like a passport for your vehicle.
It is absolutely mandatory to enter some countries with a vehicle and must be prearranged

Definition

The Canadian Automobile Association explains a Carnet de Passage as follows:

The Carnet can be thought of as a passport for your car. It offers a guarantee to a foreign government that the vehicle identified in the Carnet, if granted temporary importation status, will be removed from the country within the time limit imposed by the respective jurisdiction. In the event that the vehicle is not removed within the imposed timeframe, the country may claim from the issuing association all duties and taxes that would be required to permanently import the vehicle to that country. Using the Carnet is an alternative to leaving a cash security deposit with a foreign government to guarantee the vehicle leaves the country. It allows free movement and unencumbered access between foreign countries....

Where to get a Carnet de Passage

In almost all cases, a Carnet can be obtained from the motoring association in your home country. Ask there.

Cost

How much does a Carnet cost

Each country requiring a Carnet for entry will require a certain value be placed in bond. This amount is usually stated as some number of times the estimated value of the vehicle.
For example, if your vehicle is valued at $20,00 and the particular country you want to visit requires a Carnet of 3 times the value of the vehicle, you will have to purchase a Carnet for $60,000 to enter that country.

Do I get my money back

Yes. When the vehicle comes back to it's original country, the Carnet is cancelled, and the original bond amount is refunded (usually minus some fees)

I don't have that much cash...

Most Motoring Authorities that can issue Carnets now have an indemnity coverage option, which means you only pay a fraction of the full amount required and the rest is covered by indemnity insurance. Inquire at your local motoring authority.

Countries that require a Carnet de Passage

Unfortunately almost all lists on the internet are quickly out of date. Hopefully in the near future wikiOverland will contain this information. For each country, the entry requirements are listed.
For now, you may also want to check

• Paperwork | Horizons Unlimited
• Carnet de Passage - wikipedia (list of countires is known to be out of date)