How does it work?
CES exchanges create a directory of goods and services offered by the users registered with them, as well as a list of their ‘wants’ or requirements. When a user requires something advertised in the directory the seller is contacted and the trade takes place.
The buyer 'pays' the seller by
1. The seller entering the trade via their mobile phone or computer, 
2. Signing a trading sheet provided by the seller
3. Handing over a cheque-like trading slip that records how much the buyer is agreeing to be debited by the seller for the goods/service delivered. The slip is either handed by the seller to a group administrator who will enter the amount into the computerised system, or the information is entered directly by the seller.
Sales are recorded as credits for sellers and as debits for buyers. The central book-keeping system records the relative trading positions of the traders.
Those in credit can claim from the community goods and services to the value of their credit and those in debit owe the community goods and services to the value of their debit. Traders receive a regular statement of account that lists their trades and gives their balance at the end of the period. Information about the trading position of others prevents unscrupulous buyers from exploiting the system. Newsletters assist in building links and enhancing the sense of community.
