Google defines a link scheme as any attempt to manipulate search engines and website ranking through the use of unnatural links. What is an unnatural link? Any link that is bought, traded, or generated in a reciprocal exchange. There are other types of more complicated link schemes, but you can keep things simple: don’t try to get links that you don’t deserve. The best SEO consultants help you generate inbound links without resorting to link schemes of any kind. This involves a heavy dose of digital PR, the creation of interesting content, and elbow grease.