Invited commentary on Paley and Shapiro Are all psychological treatments for psychosis equal? The need for CBT in the treatment of psychosis and not for psychodynamic psychotherapy Nicholas Tarrier 1 *, Gillian Haddock 1 , Christine Barrowclough 1 and Til Wykes 2 1 Academic Division of Clinical Psychology, School of Psychiatry and Behavioural Science, University of Manchester, UK 2 Department of Clinical Psychology, Institute of Psychiatry, UK Paley and Shapiro conclude in their review (Paley & Shapiro, 2002) that there is clear evidence that cognitive-behaviour therapy (CBT) results in clear clinical benets for people with schizophrenia. They argue that this research could be informed by the wider psychotherapy literature, specically the ‘equivalence paradox’ and ‘investigator allegiance’, and that psychodynamic treatments for schizophrenia should be investigated and evaluated. We argue that their review of the literature is incomplete. We conclude that there is little evidence to support the ‘equivalence paradox’ generally, and where it is suggested, as in depression, this is most likely an artefact. In schizophrenia, there is consistent evidence that supportive psychotherapy performs poorly in treating hallu- cinations. We argue for improved methodology in carrying out randomized controlled trials, which would minimize bias, such as from ‘investigator allegiance’. We consider evaluation of psychodynamic psychotherapy to demonstrate equivalence to CBT as a low priority and unlikely ever to be attempted. We consider the research and clinical priorities to be the further developments of CBT and family intervention methods, which could have signicant benets for sufferers of schizophrenia and their carers. In a recent article published in this journal, Paley and Shapiro summarized the literature on psychological interventions for schizophrenia and commented on how this line of research might be further informed. There was much of interest in the paper and we welcome the opportunity to contribute to this debate and comment on a number of issues that have been raised. Psychotic disorders remain an enigma. They are extremely 365 Psychology and Psychotherapy: Theory, Research and Practice (2002), 75, 365–374 © 2002 The British Psychological Society www.bps.org.uk *Requests for reprints should be addressed to Professor Nicholas Tarrier, Academic Division of Clinical Psychology, Education and Research Building (2 nd Floor), Wythenshawe Hospital, Manchester M23 9LT, UK (e-mail: nicholas.tarrier@man.ac.uk).