Book excerpt: The problem of collateral is a daily issue for lenders and causes much debate in the development finance community. Given the difficulties experienced in arranging traditional forms of loan security, such as land or chattel mortgages, various collateral substitutes have been proposed. Among the substitutes for traditional collateral is the loan guarantee. Guarantee systems for loans have been proposed, planned and implemented in various countries. The assumption made by proponents of such a service is that the guarantee organization is either better informed about the risk of the loan than the lender or it is better structured financially to be able to manage the risk. Despite the apparent attractiveness of a loan guarantee, the empirical evidence available gives little encouragement. Nevertheless, interest in guarantees continues.