What characteristics of mutual funds do investors care about? In addition to performance and fees, we show that investors exhibit a clear preference for managers who adhere to the strategies they describe in their prospectuses. Capital flows respond negatively when funds diverge from the average holdings of their text-based strategy peer groups , but positively when they outperform those peer averages. We identify this effect using a novel instrumental variables approach, and show that funds face a delicate trade-off between keeping their promises and outperforming their peers who make similar promises.