Psychotherapy Research 9(2) 127-153, 1999 DEVELOPMENT OF PSYCHOTHERAPISTS: CONCEPTS, QUESTIONS, AND METHODS OF A COUABORATIVE INTERNATIONAL STIJDY David Orlinsky M. Helge Rennestad Paul Gerin Ulrike Willutzki Alice Dazord Hansruedi Ambühl john Davis Marcia Davis jean-Francois Botennans Manfred Cierpka o ...• o N and Nicoletta Aapro Peter Buehheim Sue Bae Christine Davidson Eric Friis-]orgensen Eunsun joo Ekaterina Kalmykova Jan Meyerberg Terry Northeut Barbara Parks Elena Scherb Thomas Sehröder Gaby Shefler Dan Stiwne Seott Stuart Margarita Tarragona Antonio Braneo Vaseo Hadas Wiseman and the SPR Collaborative Research Network N N M N M ...• r-- o o N The aim of this international study is to examine the nature, correlates, and perceived determinants of development among professional psycho- therapists from different countries and cultures at all career levels, trained in different professions and theoretical orientations. Psychotherapeutic development was conceptualized and assessed from several perspectives, including concurrent and retrospective reports by therapists and cross- sectional and longitudinal analyses of therapists' practices and experiences. This paper presents the main questions guiding the study, defines its core concepts, introduces the survey instrument, describes data collection pro- cedures, and reports descriptive and scale development data from a multinational data base of nearly 3800 therapists. Analyses provide evi- dence for the reliability and validity of direct and indirect measures of retrospected career development and currently experienced development, and their applicability to diverse groups of psychotherapists. The work of the first author (David Orlinsky) was supported in part by N.I.M.H. Grant R-0142901-01. The Portuguese data collection was supported in part by grant PCSH/C/PSII345/92 to Antonio B. Vasco, from the Portuguese National Board for Scientific and Technological Research. Authors' affiliations follow: David Orlinsky, Universiry of Chicago, Hansruedi Ambühl, University of Bem, M. Helge Rennestad, University of Oslo, lohn Davis, University of Warwick, Paul Gerin, INSERM, Lyon, Marcia Davis, North Warwickshire Health Services, Ulrike Willutzki, Ruhr University-Bochum, 127