Hey, i have no idea how the Free Trade treaty applies here, but

here's an example of how complex these things can get. I'm a contract worker, paid by the hour. I"m contracted with a multinational, drawing a piece of equipment to be built in the US and installed in their plant in Korea. Right now I'm not working, waiting for a new assignment it looks like the company would have to pay South Korea income tax for my work. Now, maybe this is South Korea's way of trying to get all the design work done by South Koreans. Who knows?