The objective of this study item is to document missing elements and information with regard to the roaming architecture for Voice over IMS with Local Breakout. The present document collects and evaluates end-to-end roaming scenarios under different aspects of charging. The main scenarios presented will include mobile originating calls with and without the use of the loopback mechanism and mobile terminating call scenarios. It will analyse operator requirements in consideration of the roaming scenarios and the existing Charging specifications The conclusions are presented in a further clause with assumptions made and proposed further proceedings on that issues.