This master's thesis examines whether hedge fund performance is due to manager skill or luck. The document provides an abstract that summarizes the thesis. It applies a false discovery rate methodology to measure the proportion of lucky funds among hedge funds with statistically significant returns. The results show that hedge funds outperform due to skill more than luck, and underperform due to being unlucky rather than unskilled. Event driven, relative value, and multi-strategy funds have very low false discovery rates, implying manager skill. CTA, relative value, and short bias funds have higher false discovery rates when underperforming, implying more luck than skill. Small funds' outperformance is also more due to luck, while large funds' underperformance is