O and P visas are designed for those who have exceptional abilities in a number of different areas. They can be used only by non-immigrants, providing a way to enter the country and work legally, putting those abilities to use.
The O visas come in two varieties, the O-1 and O-2. They can be filed by both employers and agents. This category is for those whose abilities lie in the fields of education, science, business, art, athletics or television. They can also be used for work in motion pictures.
The P-1 visas are also available for those who are tremendous athletes, whether they play on teams -- such as soccer or football teams -- or in individual sports like tennis and golf. These can also be used for entertainment groups with international recognition.
When employers file the applications for the visas instead of agents, it's important for them to remember that every employer has to file its own visa. A person may be entering the country to work for multiple companies or in a number of different positions. It is not enough to get one visa for one employer, of either the O or the P variety, and then just to switch positions after entering the country. The visas are specific to the jobs being done, so each employer has to apply and be granted one before employment can begin.
Filing these petitions properly is incredibly important. At the same time, the process can be quite complex. You don't want to make mistakes or be denied based on something that could have easily been corrected, so be sure you fully understand the legal process and the visa paperwork.
Source: U.S. Citizenship and Immigration Services, "Memorandum," accessed Aug. 19, 2016