The P-Visa a non-immigrant visa that is specifically for athletes, artists, entertainers and their coaches or support staff, to come to the U.S. for a single event or a series of events. There are essentially three sub-categories of the P visa, and the length of time they are issued depends on the period of time required to complete the event, activity or performance.
A P-2 visa for artists or entertainers is valid for a time period required to complete the event, activity, or performance, and should not exceed one year, but extensions in one-year increments are allowable.
The P-2 visa is available to artists and entertainers either individually or as part of a group (needs to be an integral part of the performance of the group for at least 1 year year or a substantial period of time), who seek to perform under a reciprocal exchange program between an organization in the U.S. and an organization in one or more foreign countries.
The duration of the visa will depend on the category you fall into, but for example a P-1 will be issued for the duration of the activity up to five years, and there are extensions available for a maximum of ten years.