Methods, systems, and apparatus, including computer programs encoded on computer storage media, for order routing. One of the methods includes receiving a request for quote from a user, the request for quote indicating that the first user is to be anonymous during the negotiation. The method also includes selecting counterparties to receive the request for quote. The method also includes sending the request for quote to the selected counterparties absent revealing the identity of the user. The method also includes receiving prices from the counterparties, each price associated with a counterparty. The method also includes presenting the prices to the user.