This document provides a mapping of technical issues associated with development of the Next Generation Nuclear Plant (NGNP) intermediate heat transport loop and nuclear hydrogen plant support systems to the work that has been accomplished or is currently underway. The technical issues are ranked according to priority and by assumed resolution dates. Due to funding limitations, not all high-priority technical issues are under study at the present time, and more resources will need to be dedicated to tackling such issues in the future. This technical issues map is useful for understanding the relative importance of various technical challenges and will be used as a planning tool by the NHI technical leadership for future work package planning. The technical map in its present form will be discontinued in FY08 and will be folded into a larger NHI System Interface and Support Systems project management plan and scope baseline statement in FY08.