Over the past few years the German and Austrian construction industries have been confronted with increasing complexity in projects, a situation, which has resulted in a significantly higher number of construction claims. The lack of an effective documentation system and a standardized claim management system has led to a growing number of disputes and legal cases. To develop a standardized claim management system, it is essential to understand and analyze deviations in the as-planned vs. the as-built occurring during project execution. A standardized system may assist in the quantification of impacts of different deviations and change procedures in future projects. This paper focuses on deviations and their effects occurring during project execution, as well as possible disputes arising from them. Further research is necessary in order to develop an effective standardized claim management system.