What is the criteria for Olympic athletes?

Question

What standards need to be met in order for an athlete to play for a specific team? I see many foreign born athletes playing for the US as well as many current US citizens playing for thier home countries. How does it work?

Answer 1

When I hear Slovenia or Germany or Finland, I expect to see a Caucasian athlete, but they turn out to be African runners or jumpers or Chinese paddlers or shuttlers.

Answer 2

You only have to be a naturalized citizen of that country.  Some like that US basketball player that is playing for Russia, gets fast tracked to be a Russian citizen for these games.  In her case, she didn't make it onto the US squad, so she offered her services to Russia.