We develop a model of mutual fund manager investment decisions near the end of quarters. We show that when investors reward better performing funds with higher cash flows, near quarter-ends a mutual fund manager has an incentive to distort new investment toward stocks in which his fund holds a large existing position. The short-term price impact of these trades increase the fund's reported returns. Higher returns are rewarded by greater subsequent fund inflows which, in turn, allow for more investment distortion the next quarter. Because the price impact of trades is short-term, each subsequent quarter begins with a larger return deficit. Eventually, the deficit cannot be overcome. Thus, our model leads to the empirically observed short-run persistence and long-run reversal in fund performance. In doing so, our model provides a consistent explanation of many other seemingly contradictory empirical features of mutual fund performance.JEL Classification: D82, G2, G14. Keywords: turn-of-quarter effect, painting the tape, mutual fund performance, investment distortion. * Richard Martin's master's essay under the direction of the first author was a building point for this research. We greatly appreciate Harvey Westbrook Jr.'s significant contributions to early drafts. We are also grateful for comments received from two anonymous referees, Chris Brooks, Murillo Campello, Duane Seppi, and seminar participants at Queen's University, St. Francis Xavier University, the Northern Finance Association meetings, the Financial Management Association European meetings, and the Multinational Finance Society meetings. We develop a model of mutual fund manager investment decisions near the end of quarters.We show that when investors reward better performing funds with higher cash flows, near quarter-ends a mutual fund manager has an incentive to distort new investment toward stocks in which his fund holds a large existing position. The short-term price impact of these trades increase the fund's reported returns. Higher returns are rewarded by greater subsequent fund inflows which, in turn, allow for more investment distortion the next quarter. Because the price impact of trades is short-term, each subsequent quarter begins with a larger return deficit. Eventually, the deficit cannot be overcome. Thus, our model leads to the empirically observed short-run persistence and long-run reversal in fund performance. In doing so, our model provides a consistent explanation of many other seemingly contradictory empirical features of mutual fund performance.JEL Classification: D82, G2, G14.