Most SEO companies emphasis on back linking. The more links you get from other sites with the right keyword, the higher you’ll rank. It’s a simple principle. However, there are many ways to do this wrong. Doing it the wrong way could get your site penalized or actually rank lower than you intended.
Think of this as a marathon more so than a sprint. If you’re consistent with your link building, you will naturally rank higher. This is what Google is looking for anyway.