Assertive outreach services have been central to community mental health policy within the UK. These multidisciplinary teams were established to engage with service users who have severe and enduring mental health problems and have found traditional community services unable to meet their needs. Mental health nurses have a pivotal role in these multidisciplinary teams, yet the nature of these relationships from the perspective of those who work in and receive care is poorly understood. This study set out to explore the nature and meaning of engagement for practitioners and service users within assertive outreach services. A qualitative approach, informed by philosophical hermeneutics, underpinned the study. Participants were recruited from a single assertive outreach team in the UK. To be eligible for the study, mental health practitioners needed to be employed within the assertive outreach team. All service users residing in the community and receiving care from the team were also eligible for inclusion. In total 14 interviews were conducted with mental health practitioners and 13 with service users. Data analysis was informed by Turner's method. Four themes emerged from the data; contact, dialogue, transformation and shared understanding. Meaningful engagement was found to manifest itself through experiences such as providing and receiving practical assistance, having a genuine two-way conversation and valuing the experiences and personal attributes of the other person. The findings indicate that engagement is an active, dynamic and skilled process, which leads practitioners and service users to transform together to create a new relationship. © 2011 Blackwell Publishing.