Changing professionals' attitudes toward seclusion is seen as an important condition to reduce its use. The purpose of this study was to determine whether professionals from a mental health institute in the Netherlands changed in their attitudes toward seclusion after implementation of a multifaceted seclusion reduction program. Professionals working on four acute admission wards filled in the Professional Attitudes Toward Seclusion Questionnaire (PATS-Q) before and after a seclusion reduction program. Changes were analyzed by comparing mean scores on the PATS-Q. After the program, professionals scored significantly higher on 'ethics' and 'more care'. As expected, no change occurred on 'reasons' for the use of seclusion. In addition, no significant changes were found on 'confidence', 'better care' and 'other care'. Significant changes in professional attitudes concerning the ethics of using seclusion and involving issues of more care were observed after a seclusion reduction program. Mental health professionals moved in the direction of 'transformers', indicating an increased criticism of the practice of seclusion and increased willingness to change their own use of seclusion.