Have you ever wondered why some people just can’t get out of their depressing mood? Do you find it hard to understand people who eat for comfort and then complain of getting fat? Do you have someone in your group who displays split personality? Is your sibling antisocial? Well, the answer for all of the above is psychological disorder. It isn’t that people with psychological disorder look different from the rest – they simply act differently. And it is to help them come out of their psychological problems that we have psychologists. Psychologists are professionals who are well-equipped to treat people with behavioural and personality disorder. They evaluate and study the mental process and are clinically qualified to help sufferers cope effectively from life issues and mental health. As such, psychologists are often referred to as doctors of mental health. In our world today, psychologists or psychiatrists, as they are often called, have started playing an important role in the society, given the stressful life. Every country today has a pool of psychologists who are uniquely qualified to help people come out from their stress and America is one such country. It boasts of having clinically proficient professionals who are qualified to help people suffering from psychological issues. Given here are the profiles of some of the greatest American psychologists – their life, study, work and contribution in the society.