In general, a computer-implemented method of managing data exchange includes registering a plurality of data sellers with a computer-implemented data exchange; registering a plurality of data buyers with the computer-implemented data exchange; mediating data sharing arrangements between pairs of the buyers and sellers, the arrangement defining prices and permitted uses of data provided by a data seller to a data buyer; and enforcing, on behalf of the data seller, restrictions imposed by the negotiations on data use by the data buyer.