We show that multimarket contact (MMC)—the extent to which the same dealers interact across many securities—disciplines the pricing of corporate bonds. In a repeated-game model, where dealers alternate between supplying and demanding liquidity, a dealer that is tempted to widen spreads for a short-run gain is deterred by the prospect of facing wider spreads when next demanding liquidity. MMC pools this discipline across securities: a deviation in one security triggers retaliation in the others. The model predicts that higher MMC for one dealer lowers spreads for all dealers active in that bond, with the largest effects when adverse selection is high or trading is infrequent. Using TRACE data, we exploit within-bond-month variation across dealers and within-dealer-month variation across bonds. Higher MMC compresses interdealer spreads, with reductions passed through to customers. A shift–share instrument based on the sharp increase in investment-grade bond issuance during COVID confirms the result.