Practically every marketing trade journal is buzzing "word of mouth" these days. Many practitioners consider peer-to-peer communication to be the new panacea for many, if not all of the problems that advertising is currently facing. The academic community has also rediscovered the subject as one that is highly relevant and crying out for scientific investigation and substantiation. However, four years ago, when Martin Oetting began his research project, this was not at all clear. He was intrigued by the early, weak signals he had picked up during his professional career in advert- ing, and he...