Successful services depend on the meeting between customers and companies to be one of co-creation. The chapter provides an overview of current perspectives on co-creation. The author discusses these in terms of trust. In particular, a synthesizing perspective is provided on co-creation of service design and co-creation of service value, seeing these as end-points in a continuum. The author discusses co-creation and trust as mutually dependent. Exploring one of the roots of co-creation, participatory design, five principles for establishing trusting relations are explicated and discussed relative to co-creation practices in current service innovation. The principles include the need to leverage multiple stakeholders and interests, establish common ground, observe practice, encourage skill-based participation, and aim for a greater good. The role of co-creation and trust in service provision is illustrated with an example from peer-to-peer redistribution markets.