On Wal-Mart's corporate website, under News and then Statements (the site makes it almost impossible to link directly inside, no doubt on purpose), is this gem:
As you may know, Wal-Mart makes an exception to its anti-union stance in that bastion of freedom, China. See this BBC story for the basic facts. (The Chinese "union" is controlled by the government, and "represents" workers accordingly.)
Then read Harold Myerson's Washington Post column (reg req) to understand the meaning of it all, which I summarize with this apt quote: " When a company such as Wal-Mart is so plainly comfortable with authoritarianism abroad, it tells you something about that company's values at home."