The Cambodian riel is pegged at 4000 to the USD; most prices are stated in dollars.
I rushed to catch a bus hungry, and then ordered a sandwich through the window. The vendor held up one finger so I gave him $1. He chased after the bus to give me 3000 riel change!
septimus–love it! Good story.
Also, you can get US dollars from ATMs in the cities and tourist areas of of Cambodia.
You might want to read up on currency board systems. Here’s wiki: Currency board - Wikipedia
The Hong Kong dollar being the most well known example (and by extension the Macau pataca). You may think China rules HK and Macau, but it’s the US dollar and interest rates that rule their money.
Currency boards simplistically take USD, put it into a reserve, and then issue local currency against that reserve. A currency reserve cannot be broken by speculators because a) interest rates jack up and b) worst case scenario they just replace the local currency with the dollars in reserve.
IIRC, when the hong kong dollar came under attack during the Asian crisis, the attack last less than 48 hours and overnight interest rates went up over 1000 per cent. (When rates go up that high, it becomes prohibitively expensive to finance the attack.)
Yes Cambodia is very confusing when you pay in dollars and they give you riel or a combination of both in change. To some extent riel acts as cents for when something isn’t a round-dollar figure. You have to concentrate when you’re not used to it!
When I was in Israel 15 years ago, for any purchase under $20, a shekel equaled a quarter, and American dollars happily accepted. (tourist areas)
I just spent 10 days in Costa Rica and never changed money. Some (not all) ATMs allow withdrawals in either colones or dollars.