Viktor Emil Frankl (26 March 1905 dash; 2 September 1997) was an Austrian psychiatrist and Holocaust survivor, renowned for founding logotherapy, a form of psychotherapy that emphasizes finding personal meaning in life as the primary motivational force. Frankl's approach is recognized as a significant contribution to existential and humanistic psychology, and it has been referred to as the Third Viennese School of Psychotherapy, following the theories established by Sigmund Freud and Alfred Adler.

Throughout his career, Frankl wrote 39 books, many of which have been influential in the field of psychology. Among these works, his most famous book, Man's Search for Meaning, stands out as a bestseller. The work is autobiographical and is based on his harrowing experiences in various Nazi concentration camps during World War II. Through this book, Frankl shares a powerful message about the psychological importance of seeking meaning, even in the most dire of circumstances, providing readers with a compelling reason to persevere through adversity.

Frankl's theories have been a cornerstone in the development of existential therapy and have established him as one of the key figures in the field.