In this paper we discuss support for solving complex “wicked” planning problems by dialogues and explanations. Wicked problems are essentially imprecisely formulated problems, i.e. those that do not have a clear goal, well defined methods, and are subject to personal opinions of involved stakeholders that may be changeable. The method contains the following steps: (1) Reducing the complexity of the problem by the selecting a specific concern; (2) Obtaining a user defined ideal plan, called a prototype; (3) Comparing the actually generated plan and the prototype by a similarity measure. This will be aided by an explanation oriented dialogue. A major problem for the explanation is that we need to explain the result of an optimization procedure which excludes classical parsing oriented methods. The approach is generic and was instantiated in release planning, investment, and urban planning. We have simplified the original problems significantly in order to illustrate the principal approach.