Mina Spiegel Rees (1902-1997) was an American mathematician who had a significant impact on mathematical research and eduction in the United States. She received a PhD in mathematics at the University of Chicago, writing under the direction of L.E. Dickson. She was the head of the Mathematical Sciences Division of the Office of Naval Research during World War II and was the Dean of Graduate Studies at CUNY after the war. This book covers in depth Rees' many contributions to the US mathematical scene.