Collaboration is key to high performance and better outcomes. Contract forms like alliances and early contractor involvement promote collaboration by aligning goals and sharing risks/rewards. Research on alliance projects in New Zealand found they delivered non-cost benefits like safety, quality and stakeholder satisfaction by developing a collaborative culture. Challenges include selecting the right people and financial models, and sticking to collaborative principles when issues arise. Airports may benefit from collaborative contracts for time-critical or complex interface work like airside/landside projects. Traditional models can also succeed with focus on collaboration.