TN - NAFTA Professional
P Visa - Entertainers and Athletes
R1 Visa - Religious Workers

The E visa is useful for business owners, managers, and employees who need to remain in the United States for extended periods of time in order to oversee or work in an enterprise engaged in trade between the United States and a foreign state or that represents a major investment in the United States

There are three requirements for obtaining an E visa:

1. A treaty must exist between the United States and the foreign country.
2. Majority ownership or control of the investing or trading company must be held by nationals of the foreign country
3. Foreign country citizenship must be held by each employee or principal of the company who seeks E visa under the treaty

Duration of stay
Although an initial period of stay of two years is granted, the period can be extended almost indefinitely—as long as the alien affirms that he or she will leave the United States when the period of authorized stay ends.

The procedures for obtaining the E visa?
Unless the foreign national is in the United States, the usual way to obtain the E visa is to apply for a visa at a U.S. consulate outside the United States and then be admitted to the United States with the E visa.