Required Navigation Performance (RNP) is similar to Area Navigation (RNAV); but, RNP requires on-board navigation performance monitoring and alerting capability to ensure that the aircraft stays within a specific containment area.
Not only does RNP offer safety benefits with precision and accuracy, it reduces the cost of inefficiencies such as multiple step-down non-precision and circling approaches (saving fuel and time).
This type of approach can be seen at Madeira (LPMA) for example:
Photo Source: USAC Aviation, Jeppesen
