You decide we make it.
The client decides what it wants to build, the timeframe in which it should be built and how much it should cost.
Once the contractor has won the work from the consultants, construction begins on site. Contractors ensure the project is built to the agreed quality, budget and timeframe. They take instructions about the design from the design consultancy and run any design-related problems past them.
Final delivery of the project as per agreement norms.