The Connecting People Intervention (CPI) is a social care intervention which aims to support people to enhance the resourcefulness of their social networks. This implementation study utilises an opportunity provided by the Think Ahead programme, which trains social work students in the CPI, to evaluate the training, processes and support required to implement it with high fidelity in community mental health teams (CMHTs). Using a quasi-experimental design, a set of implementation tools (CPI practice guidance, a user guide, training and implementation manuals) will be provided to social care staff and service users in six CMHTs in six NHS Mental Health Trusts participating in the Think Ahead programme. Waiting list control teams from the same Trusts, which do not implement the CPI during the course of this evaluation, will be selected to evaluate the relative effectiveness of the implementation. Teams will be selected on a pragmatic basis in this natural experiment rather than by randomisation. Full data will be required from 192 participants at baseline and 12 months follow-up with the principal outcome being access to social capital. A qualitative study will explore the process of implementation to enable us to refine the CPI practice guidance, user guide, training and implementation manuals, which will form the core outputs of the project and be made freely available.