Psychological assessment is a process that involves the integration of information from multiple sources such as psychological tests, history, description of current symptoms and problems by either self or others. Psychological tests are standard measures devised to assess the behaviour objectively. The nurse should have knowledge of all the psychological tests which will enable her to clarify to the patients and relatives the doubts regarding the psychological tests they have to undergo. To provide a basic understanding of such issues to a nurse, a description of characteristics, development, types, uses, limitations and interpretation of psychological tests has been provided. Detailed information is also provided on role of a nurse in psychological assessment.