This chapter describes how mortgage originators hedge the gain-on-sale income from their mortgage pipeline using to-be-announced (TBA) securities. The timeline from rate lock to funding, which often ranges from 15 to 60 days, exposes originators to interest rate risk. To mitigate this, they enter TBA contracts corresponding to the characteristics of the mortgages they are originating. The case explores the mechanics of the TBA market, which is a critical component of the secondary mortgage market, allowing originators to manage risk efficiently and maintain profitability. A practical illustration demonstrates how originators use TBA contracts to hedge pipeline risk, balance liquidity needs, and navigate market volatility, ensuring stability during periods of fluctuating rates.