If this "Primer on the International Aspects of International Priority Communications (IPC) Policy” establishes a common understanding of what IPC is and is not, so that the other contributed papers to this Summit can then consistently build on that foundation, then it purpose has been achieved. It is imperative that high priority critical communications be served across international boundaries. Under severe conditions such as a disaster or crisis, the communications networks may well be offered much more communication traffic than the bandwidths can support. In such cases some, or most, traffic must be shed allowing other communications proceed. Rather than a random or arbitrary mechanism for discarding a subset of the communications, a system may have a means of marking critical communications such that a higher level of probability of completions exists for such communications as compared with other message attempts on the same network. Determination of Critical Infrastructure is a matter of local policy and may include power, water, finance, and civil order as some examples. This paper addresses aspects of such Priority Communications when the origination and destination points are in different nation's networks (international). This paper does not address the selection and transmission mechanisms used within a national network as this is a matter of local policy.