New Product Development (NPD) processes are considered most challenging, involving major risks due to unknown or unforeseen obstacles, in terms of technology and business risks. The actual process activities which depend on the evolving product knowledge could be determined only during process execution. Thus, process planning is inherently dynamic and requires adaptation to product knowledge changes as well as other changes. Current Workflow tools can support ad-hoc changes, but do not support the planning of process dynamics and the execution of such dynamic process changes as they unfold. The current article presents a novel system framework for managing dynamic process planning changes resulting from changes in customer requirements, product structure, product parametric dependencies and constraints, as well as ad-hoc changes. The proposed framework comprises: process planning, incorporating the Design Structure Matrix (DSM) method; business rules for interprating the DSM-based plan to process plan; dynamic process plan changes; and implementation of changes into Run Time process simulation.