Over-the-counter (OTC) markets dominate trading in many asset classes. Will electronic trading displace traditional OTC “voice” trading? Can electronic and voice systems coexist? What types of securities and trades are best suited for electronic trading? We study these issues by focusing on...

All option trades must occur on exchanges, which typically offer auctions that improve prices over existing quotes. Wholesalers, that purchase orders from brokers, initiating auctions must be willing to trade at the existing best quote or better. For S&P500 stocks, auctions are 23% of options...

We develop a network-flow approach for characterizing interim-allocation rules that can be implemented by ex post allocations. Our method can be used to characterize feasible interim allocations in general multi-unit auctions where agents face capacity constraints, both ceilings and floors....