In general, the closer information to its source, the more accurate and timely the info is likely to be, for at least 3 reasons:
1. the source of the information, by definition, the most accurate.
2. Extra delay and opportunity for error between the source and directory are eliminated
3. Depending on the info and the application, the source is likely to be the party most motivated to maintain the information correctly.

Based on this assumption, Penrose can integrate multiple directories spread out from a single department, multi-departments or even from other organizations, leaving the task of updating their directories to the respective owners.