Rolling Wave

Rolling wave is an iterative scheduling technique that uses progressive elaboration to plan the project as it unfolds.  This is typically used when there is not enough information to create a complete schedule up front.  This is a cyclical process where the project manager fills in details in the WBS and schedule to where there is clarity and keeps it high level where there is no clarity, executes, re-plans to where there is clarity, executes, and continues until there is clarity to the end.  This allows work to progress on current and short term tasks while planning is still going on for future work packages and tasks.

Rolling wave planning is typically used in projects with high uncertainty where appropriate risk management is critical.

It is still essential to create milestones and assumptions for the entire project.  This will explain to stakeholders what to expect and why the rolling wave technique is being used. 

Ensure appropriate management of scope relative to project success criteria to prohibit the project from dragging on with scope creep.