In the product development process testing and validation is necessary to certify the function of the product. but it is time and cost extensive. A high ratio between output and input effort has to be aimed. To reach this effect a hierarchy of test levels is sensible. This paper shows an approach to describe and map the transferability of boundary conditions between these scale levels and model layers. The chosen scale levels are material. structure and product level and the model layers are reality. physical and virtual models. The challenges of the transferability of boundary conditions will be shown for three research topics. static testing for cylinders. optimization of sandwich inserts and dynamic testing of cabin interior.