We present the Intelligent Application Oriented System (IANOS) resource broker models and internals. The aim of IANOS is to provide an understanding of and a solution to the problem of how to find the best resource for a given submitted application in order to optimally use a set of HPC resources (an HPCN Grid). Best in the sense “at a given moment and for the requirements of that specific application”. The heart of IANOS is a cost model that minimizes the overall submission cost such as execution time cost, waiting time cost, licenses cost, energy cost, etc. To estimate the execution time cost, a model predicting the performance of an application on a resource where INAOS is installed is provided. This model is based on a parameterization of the application and the resources. IANOS has been deployed and tested successfully on an international testbed across Switzerland and Germany.