This text features a compilation of approximately 900 problems which have appeared on the preliminary exams at Berkeley University. It provides a source of problems and solutions for every mathematics student who plans to undertake a PhD. The problems are organized by subject and ordered in an increasing level of difficulty. Tags with the exact exam year provide the opportunity to rehearse complete examinations. This second edition contains approximately 120 new problems and 200 new solutions. It is an ideal means for students to strengthen their foundation in basic mathematics and to prepare for graduate studies.