Aaron Beck, whose work in developing the theory and practice of cognitive therapy brought about a revolution in the treatment of mental disorders, has passed away at the age of 100. Beck’s pioneering approach to mental health was recognized with a 2006 Lasker Clinical Medical Research Award. Cognitive therapy, the Award citation stated, “has transformed the understanding and treatment of many psychiatric conditions, including depression, suicidal behavior, generalized anxiety, panic attacks, and eating disorders.” Beck’s research, which he launched in an era when Freudian analysis and medication-based therapy were dominant approaches in mental health, proved to be a paradigm shift in the field. As the 2006 Lasker Award citation noted, “cognitive therapy has proven as effective as medication in alleviating depression and even more effective in reducing relapse and recurrence.”