The interest in construction partnering has increased during the last decade. Much research have, however, found that cooperation and its benefits are not easily obtained, partly due to a lack of understanding of the partnering concept and when and how to implement it. The aim is therefore to increase this understanding by investigating three research questions: 1) What is partnering? 2) When should partnering be used and to what extent? 3) How should partnering be implemented? A thorough literature review and four case studies are utilized to develop a definition of partnering and discuss when and how partnering should be implemented through cooperative procurement procedures. Partnering is defined as a cooperative governance form that is based on core and optional cooperative procurement procedures to such an extent that cooperation-based coopetition is facilitated. Mandatory core procedures are: soft parameters in bid evaluation, compensation form based on open books, and usage of the core collaborative tools start-up workshop, joint objectives, follow-up workshops, teambuilding, and conflict resolution techniques. Complementary optional procedures are: early involvement of contractors in concurrent engineering, limited bid invitation, joint selection and involvement of subcontractors in broad partnering teams, collaborative contractual clauses, incentives based on group performance, usage of complementary collaborative tools (e.g. partnering questionnaire, facilitator, joint risk management, joint project office, and joint IT-tools), and increased focus on contractors' self-control.