number portability A puzzle unlocking voice opportunities FOLLOW THE CUSTOMER It is hard to remember the days before number portability, and in fact, the right to take your telephone number with you as you choose a different operator has now been in existence for more than 20 years. However, for most of that time, international voice carriers have largely ignored the implications of portability, choosing instead to simply route voice calls to the operator that was originally assigned the number blocks. In effect, they have been handling the international delivery of the voice calls and leaving the final routing decision on how to find that specific customer to their in-country partner.