Landuse dynamics in the real world are connected to the ecosystem as well as the economic system, both of which are very complex in nature. Constructing models that produce reliable quantitative results about these dynamics is therefore a very ambitious task. One aim of this article is to make a first proposal for set of validation guidelines for the land use modeling community. While agreeing about standards for land use model validation may in itself be a major step forward, the even bigger challenge is to put this theoretical agreement into effect, i.e. not only to talk about good scientific practice but to change the real processes of model evaluation and development according to those guidelines. Therefore we present a set of tools that we have developed for validating the economic landuse optimization model MAgPIE. It is designed in a way that it can also be used by other land use modeling groups.