This last phase involves the implementation of the Action Plan and its realization on the basis of the specifications. Implementation work is awarded to the contractors and other parties and the process of realization is set in motion. Depending on contents and character of the planning specific parts of a plan (technical, institutional) may be implemented. In the course of this phase, it may become clear that additional studies are needed in order to achieve the desired end result. At the end of this phase, a new situation will have been created and this will need to be managed and maintained.

After some time, the new situation may itself need to be re-examined as a result of changing social trend or the identification of new problems. The planning process can start again from the beginning, often with different starting points and conditions. All the work that will be set in motion by the authorities (e.g. research, discussion memo's etc.) will help the implementation and realisation of the ICZM-plan.