Collaboration in construction projects has become a primary requirement in common delivery methods, especially in the detailed design phase to achieve value for the client. The involvement of multiple organisations, such as the client, architects, design consultants, project managers, contractors, and subcontractors, increases the complexity of implementing successful collaboration. Recent studies have focused on the financial aspect of collaboration but undervalued the social dimension which reflects behavioural actions that can lead to goal misalignment. There is less known about the highly dynamic nature of collaboration at a project level between participants with different views, objectives, and working practices. Through a study of two interdisciplinary teams in the detailed design phase of large-scale construction projects, participants' perceptions of collaboration were analysed to reveal that participants have different ways of viewing their collaboration, ranging from facilitation factors, working processes, and outcomes. The study advances the theory of collaboration in design management by adopting an inter-organisational practice-based perspective to assess collaboration. The findings suggest a more tailored management approach based on understanding the processes and outcomes and regular monitoring of the behaviour actions for collaboration to succeed.