Abstract
This article discusses the empirical relevance of what is considered two prinicipal contributions to the new institutional economics–the contributions of A. Schotter and O. Williamson – and draw three general conclusions. First, it is argued, on the basis of a comparison of the above mentioned two contributions to new institutional economics, their empirical relevance cannot be discussed in general but must be based on separate analyses of the two contributions and will depend on the institutions which are analysed. Secondly, that it is especially within analyses of consequence and design of institutions that the Williamson-approach to new institutional economics presently has something to offer while there seems to be rather limited possibilities for application of the approach of Schotter. Thirdly, that in their future development, the two contributions can probably both mutually benefit each other and benefit from an integration of elements from other institutional theories.