Ian Parker is one of the most important contemporary critics of the discipline of psychology. A prolific writer, with over 25 books to his name, he has a formidable reputation in the fields of critical psychology, Marxist psychology, and psychoanalytic theory. He is a fellow of the British psychological society, Emeritus Professor at the University of Leicester, and the managing editor of the Annual Review of Critical Psychology. Parker is also a practicing psychoanalyst analyst and a member of the Centre for Freudian Analysis and Research and the London Society of the New Lacanian School.

His career reflects the principles he talks about – the importance of challenging powerful institutions and the need for collectively mobilizing against discrimination and exploitation. As the "Psy-disciplines" face increased scrutiny for involvement in past abuses, continued collusion with powerful and unjust institutions, and deep criticisms over current psychological research and practice, Parker's work has particular relevance.

His criticisms of psychology and psychiatry started from his university days as a student. He observed that while other social sciences were critical of their received knowledge and open to contributions from the civil rights and women's movements, psychology continued to reinforce old power relations and pathologized these same social movements. Since then, Parker has become one of the most well-known critics of mainstream psychology, and his work repeatedly questions the role of ideology and power in the field. These contributions are evident throughout his writing, including his four-volume 'major work' Critical Psychology (2011) and a Handbook of Critical Psychology (2015). He is currently the editor of the 'Concepts for Critical Psychology' series for Routledge.