“The theme park Architects and Engineers work in tandem with the Creative design team to begin a high-level evaluation of their early concepts. At the end of the Concept Phase slightly more refined deliverables are provided to the Owner, along with a slightly more detailed project estimate and schedule, for their review. If the Owner agrees to move forward with the project, the design team is given an incremental additional design budget for the next phase of design.” -themeparkarchitect.com

Here are a combination of videos about it: