 <p>I don't have a real answer myself, but your question reminded me of this post:</p> <blockquote> <p><a href="http://stackoverflow.com/questions/4964344/selenium-doesnt-work-with-cucumber-capybara-out-of-the-box-macosx">Selenium doesn't work with Cucumber/Capybara (out of the box) - MacOSX</a></p> </blockquote> <p>Where the questioner shows how he used ruby-debug to figure out why a missing dependency was helping selenium fail to open the browser. </p> <p>Hope this helps!</p>