We asked Rand Fishkin, SEOmoz's CEO, to give us his views on backlinking strategies and how to identify white hat versus black hat backlinks. Here is Rand's commentary on this subject.

Separating black hat from white hat link building is no easy task. It's generally the case that links that require payment are in the black hat territory, yet buying a listing with the Better Business Bureau or joining a local Chamber of Commerce that requires a membership fee can get you a great, white hat link, yet have a direct payment associated with it.The best method we've found to think about black vs. white hat links is to consider the intent. If you're acquiring a link through any method (buying, asking, cajoling, trading, etc.) with the primary intent of manipulating the search engine rankings, you're likely in a danger zone. If, instead, you're either producing content that will naturally attract links or marketing your site to those who have a natural interest in sharing/spreading your works, you're in the clear.  
Some forms of link acquisition will always be black hat - hacking, UGC-spamming (blog comments, forums, guestbooks, Q+A sites, etc.), most forms of paid linking and text link advertising, link farms and many forms of reciprocal linking. These are nearly always intended to manipulate search results, rather than add a valuable node to the web's link graph that real human users will find useful and valuable. Great white hat link methodologies are nearly infinite (limited only by your marketing creativity), but include natural link acquisition through content, social media links from people/sites referencing your material, content syndication, producing badges/widgets/embeddable content, promoting link-worthy content to link-likely audiences such as bloggers, speaking at conferences and events where a profile link is included, publishing papers/books/guides on sites that offer links back, investing in research that others cite in their own publications and many, many more. At SEOmoz, we universally recommend white hat link building over black hat, not for moral or ethical reasons, but because, practically speaking, white hat links continue to add value forever, while black hat links may not work, even the day they're created. The high risks and limited life expectancy of the rewards mean that for virtually every web business, save those that have a "churn-and-burn," temporary ranking goal, black hat link building simply doesn't make sense. Rand Fishkin, CEO of SEOMoz

  Check out our recent posts on 10 link building ideas you can do in a day and on effectively using backlinks for SEO success.