Freud shares several commonalities with post-Freudian thinkers; they built upon his work and expanded the areas that were in need of such development. Karen Horney and Carl Jung were two post-Freudian thinkers whose work on different aspects of Freud's theory of psychodynamics increased the range of Freudian theory and clarified or fixed several points that were muddled or incorrect. Freud's theory of psychodynamics indicated that sexual instincts were the most important aspect of the formation of a person's personality. Freud discussed the Oedipus Complex, ensuing guilt and the problems stemming from following repression of such childhood memories. He detailed several stages of development, relating all of them to one sexual foundation or another. His theory of "penis envy" with regards to women was one Horney disagreed with except in certain cases which " she conceded…did occasionally occur in neurotic women" (Boeree, Karen Horney, 2006).
Horney herself, dealing with depressions and creating a theory of neurosis to stretch over Freud's already extensive empire, dealt very much in one of Freud's branches of theory (Boeree, Karen Horney, 2006). Freud's work with the unconscious mind detailed that relatively harmless, unvented material left, housed in the unconscious, formed the basis for neurosis. He also stated that neurosis stemmed from either sexual problems or childhood trauma with a related sexual element (Quigley, 1998). While Horney disputed the claims Freud made of females and their sexuality, she also developed her own theory of neurosis, based on the ten neurotic needs. She built personality profiles based off these ten needs which form the three main neurotic coping strategies. (Boeree, Karen Horney, 2006)
Jung was a student of Freud's and studied with him extensively. He used the main core of Freud's theory of psychodynamics as a start of his own theory and branched off, dictating several major deviations from the original. Both Jung and Freud separated the psyche into parts: Freud into the conscious and unconscious mind, Jung into conscious, personal unconscious and collective unconscious. Where Freud grouped instincts in with the types of thought Jung believed belonged in personal unconscious, Jung himself believed that instinct fell in the category of "psychic inheritance" (Boeree, Carl Jung, 2006).
Besides his trio in the psyche, Jung also theorized about the contents of the collective unconscious. He called these "archetypes" and they hold similarities to Freud's theories dealing with instinct. The only major difference between them is that Jung's archetypes were supposed to satisfy spiritual demands where Freud's instincts were biological needs demanding fulfillment. (Boeree, Carl Jung, 2006)
If one were to rewrite the theory Freud composed, one should take into account the parts of his theories that have been challenged on different grounds. For example, the part of Freud's theory that deals with the Oedipus Complex seems to only have application to males in the way he wrote it. Freud himself said female sexuality is a "dark continent" (The Psychodynamic Approach).


Works Cited
Boeree, C. (2006). Carl Jung. Retrieved December 26, 2008, from Personality Theories: http://webspace.ship.edu/cgboer/jung.html
Boeree, C. (2006). Karen Horney. Retrieved December 26, 2008, from Personality Theories: http://webspace.ship.edu/cgboer/horney.html
Congress, L. o. (2007, April 2). The Individual: Therapy and Thoery - Sigmund Freud: Conflic & Culture. Retrieved December 26, 2008, from Frued: Conflict & Culture: http://www.loc.gov/exhibits/freud/freud02.html
Quigley, T. (1998). A Brief Outline of Psycho-Analytic Theory. Retrieved December 26, 2008, from http://www.http://cepa.newschool.edu/~quigleyt/vcs/psychoanalysis.html
The Psychodynamic Approach. (n.d.). Retrieved December 26, 2008, from The Psychodynamic Approach: http://www.ryerson.ca/~glassman/psychdyn.html