For a company's mission statement, visit their webpages. Mission statements are typically found under the About Us, Our Company or Investor Relations links which are often located at the bottom of a company's homepage.
An alternative way to sometimes locate a company's mission statement, and/or identify it's goals and values, is through their 10-K filing with the Securities and Exchange Commission (SEC). 10-K filings may be found in the following databases:
Need to develop a mission statement yourself? Take a look at How to Write a Mission Statement in 5 Easy Steps.