A dilemma for market organizers is created by the fact that sellers want to know as much about buyers as possible, whereas buyers rarely want the seller to have that information—not least for privacy reasons. This dilemma is affected by market organization, and market organization may also be used to try to change imbalances in the conflicting information interests. In the market for personal insurance, insurance sellers require in-depth information about the buyer’s health conditions, in order to make an accurate categorization. As this information is sensitive to buyers, however, and can potentially exclude them from the market, many buyers are concerned about sharing it. This chapter demonstrates how sellers have spent considerable resources trying to organize buyers. However, the considerable imbalance in favour of the sellers’ interests triggered buyers and their advocates to call for market reorganizations. Eventually the state reacted and reorganized the market, but only modestly so.