Website and business owners who spend money on optimizing their websites in the search engines want to know they are getting a good return on their investments. SEOs need concrete numbers to show these people to prove that the campaign is working, and that they should continue to invest in optimization. But how do you get these numbers? Jacqueline Dooley explains six metrics to use that are helpful indicators for letting both business owners and SEOs know whether a website's optimization campaign is working, and how well.