The active involvement of users of services and their families and friends into mental health care and research is essential for the success of mental health services and initiatives worldwide. Also, co-operations between mental health professionals, users and carers are needed to solve methodological problems of evaluative research and generate new models of needs-orientated interventions. However, accepting each other in a working partnership for a multiperspective evidence base is still a challenge for professionals as well as for users and relatives and friends. Changes in structures as well as in forms of communication are warranted.

In Trialogue-groups users, carers and mental health workers meet regularly in an open discussion forum, that is located on ‘neutral terrain’ - outside any therapeutic, familial or institutional context - with the aim of communicating about and discussing the experiences and consequences of mental health problems and ways to deal with them. This setting offers new possibilities for gaining knowledge and insight and developing new forms of communication. It also functions as a basis and starting point for trialogic activities on different levels - e.g. serving on quality control boards - and different topics - e.g. anti-stigma projects. In German speaking countries well over hundred Trialogue groups are regularly attended by altogether ∼ five thousand people. Trialogues are inexpensive and a great number of people seem to benefit from participation. Current ideas for the scientific evaluation of Trialogues regarding process as well as possible outcomes pose conceptual and methodological challenges.