WHEN to Manage Interfaces
This depends on a number of factors, with cost; complexity; level of technical uncertainty; number of interfacing parties (contractors, stakeholders and other organisations); geographical locations all playing a part.
At the low end of complexity, the project manager may manage interfaces alone.
At the high end there will be multiple interface managers and interface coordinators - in addition to possibly hundreds of engineers working with interface issues.
After DG1 (during the concept selection phase of a project) interfaces will mainly be between stakeholders in the project - especially where there are significant uncetainties. This when the strategy for interface management in the project should be developed, including the Project Interface Management Plan.
After DG3 (during the execution phase) is when interface management faces the biggest practical challenges and work load - mainly between contractors