Continuous planning is an approach to planning where static annual or bi-annual plans are replaced with a continually updated plan, which is revised every time an internal or external event (such as a shift in priorities, an unexpected delay in a given program or a change in the business environment) occurs.
Continuous planning is tightly linked with the implementation of Agile and Lean methodologies, which both advocate short, flexible plans that can be adapted to changing circumstances.
Whilst most studies focus on the team level, continuous planning has benefits at all levels of the organization, including the strategic, portfolio, and product levels.
see also: roadmapping related articles: lean product development: resource management vs. flow efficiency, scaling agile: how to measure progress? with johanna rothman, a primer for integrated roadmapping: an interview with ken huskins, planisware enterprise demo: the case for using roadmaps, best practices in resource planning and forecasting to improve portfolio management