Social ExchangeMoney occupies a powerful place in our lives it is a problem, a goal, and motivator, a measure of self worth and national progress, and even an influence on how we relate to each other and to nature but what happens when communities start to reinvent money and markets? Over the last twenty five years, grassroots activists in Medelln, Colombia, have used barter markets and community currencies as one strategy to re weave a social fabric shredded by