A method of project implementation in which two or more participants (usually the owner, the constructor and the lead design consultant) agree to work cooperatively by freely sharing resources, risks and knowledge during the course of the project. The object of an alliance is to achieve the project's goals more efficiently and effectively.

Some of the characteristics which are said to distinguish alliancing from more traditional contracting are: collective performance obligations of owner and non-owner participants; open book reimbursement of non-owners costs; joint, unanimous decision making by an 'alliance board'; commitment to resolution of issues without resort to litigation; sharing of risk between participants.

Also known as Partnering or Collaborative Contracting