It's still rare to find women on a bond trading desk, and rarer still to find a woman behind a bond trading platform. But Susan Estes, CEO of OpenDoor Trading, breaks the mold. Estes went from being a top female bond trader to becoming the CEO of OpenDoor, which is preparing to introduce to the market a new way to trade bonds. The platform developed by OpenDoor is designed to increase liquidity for some fixed income securities that are more difficult to trade. The new platform is set to be up and running in October.