Qualitative study that used the framework of Fourth Generation Assessment and aimed to apprehend the perception of professionals, users and family members, about the nurse's practice at a psychiatric emergency service. Data were collected from February to June 2014, involving with 15 professionals, nine users and six family members. In the data collection, non-participant observation, participant observation and individual interviews were held, using hermeneutic-dialectic circle, with analysis by the constant comparative method. The results were grouped into two main themes: The nurse as a facilitator of multidisciplinary and humanized care and; activity accumulation: limitation for nurses to work at the psychiatric emergency service. It was concluded that the use of Fourth Generation Assessment reveals the empowerment of stakeholders as protagonists of change and that the nurse's practice is essential for the humanization of care and the dynamics of multidisciplinary work.
Nursing; Emergency services, psychiatric; Nursing care; Evaluation