In the last month, I have been in both South Africa and Kenya. In each country, I just take my Canadian or Swiss bank card and stuff it into a cash machine (the things are everywhere), and the cash machine then spits the local money out at me.
The exchange rate from the cash machines is excellent - it is bank rate - and you don't have to worry about carrying large amounts of cash, or trying to buy some obscure local currency in another country.
If you want to carry cash, the US dollar is King in Africa. Just be sure to bring fresh, clean, (never torn or damaged) banknotes of the very latest series - in most places in Africa, people will not accept US banknotes with print dates of 1999 or earlier.
My suggestion is that you get about US $100 worth of currency of the country you plan to visit first prior to landing there (meaning, buy it in Europe or wherever), then use a bank card for the rest of your trip. If you carry two bank cards (a Visa and a MasterCard) that are both capable of making cash withdrawals from your bank account (not credit card advances), you will be all set. Just be sure to test out the bank account withdrawal function of the two cards thoroughly at home - sometimes the PIN numbers are different if you are making a bank account withdrawal - and notify your credit card company of your intent to travel in Africa before you leave.
I kind of suspect that Botswana and Tanzania will be equally as contemporary as Kenya and South Africa so far as bank machines (ATMs) are concerned, but I don't know for sure. As for Zambia - I think that place is kind of screwed up, I wouldn't count on finding functional ATMs there.
Last edited by PanEuropean; 2 Jun 2006 at 01:18.