Sculpting PageRank? Are you scratching your head, wondering whether I'm talking about carving a masterpiece? In a way, I am. I'll get to why that is, in a minute.

PageRank, a Google-trademarked term, is a measure of the importance of a page. It's actually a lot more than that—it is the foundation of Google's ranking algorithm (stated as such by Google on its Google Technology page). Because of the key role that PageRank plays in search engine optimization (SEO), it makes sense to make the best use of the PageRank that your site possesses.

A site's home page typically accumulates the most PageRank (or "link juice," if you want to speak in terms that include other major engines). That's because most inbound links point to a site's homepage rather than deep into the site.

How you "spend" that PageRank throughout your site—in other words, how you flow your PageRank deeper in your site—is determined primarily by your internal hierarchical linking structure. That's why having site-wide navigation that's via keyword-rich text links rather than graphical buttons is so critically important.

So where does "carving a masterpiece" come in to play? It's based on the idea that you have a way to shape how PageRank is distributed across your Web pages via more than simply changing your navigation hierarchy. It relies on a tool, provided by the search engines, called "rel=nofollow." With it, you can send your PageRank flowing through some links, but not others.

Think of your site's navigational hierarchy as your blunt instrument, and the "rel=nofollow" attribute as your scalpel.

This level of control is a relatively recent development. The "rel=nofollow" attribute was first introduced in 2005 as a way to discourage comment spammers from defacing blogs with their links and bogus comments; the use of nofollow connoted that you did not vouch for the quality of the page being linked to.

But the engines have since evolved their thinking. They realize now that rel=nofollow is a much more versatile tool than when it was first conceived. Consequently, the use of nofollow has been expanded so that it doesn't connote anything negative whatsoever, as confirmed by search engine representatives on multiple occasions (such as in this interview with Google's Matt Cutts). So now you can feel free to use "nofollows" within your own site.

With PageRank sculpting, your goal is to optimize the flow of PageRank internally in your site so that the most important of your deeper pages get a larger share of PageRank than unimportant pages.

When old, well-established pages within your site register a poor or zero PageRank according to the Google Toolbar, it's an indication that your site's PageRank is not trickling down to these pages. An absence of PageRank puts the page at a severe disadvantage in search rankings; Google will interpret it to mean that the page doesn't deserve to rank.

(Note that the readings from the Google Toolbar are several months old and a very loose approximation of the page's true PageRank as it is used in Google's ranking algorithm, so take the toolbar's readings with a grain of salt.)

A common starting point for PageRank sculpting is the "nofollowing" of site-wide links to low-value internal pages such as Privacy Policy, Security Policy, Copyright Notices, Disclaimers, Order Status, Customer Help, Testimonials, Email Us, About Us, View Cart, Check Out, My Account, FAQ, and Shipping Info. This technique is valid for low-value outbound links too, such as "Click to Verify" VeriSign and HackerSafe seals. Doing so will save a larger share of PageRank for the remaining links to your more important pages (e.g., category pages).

Let's look at an example of how you can incorporate the "rel=nofollow" attribute in the link to your Privacy Policy page (assuming you don't care about ranking well for "privacy policy"):

<a rel="nofollow" href="https://www.yourwebsite.com/privacy.htm>Privacy Policy</a>.

It's that simple.

But here's a more powerful example. Imagine an e-commerce site with category pages that contain three links to every single product page—the product name as a text link, the product image thumbnail as an image link, and the words "View Product" as a text link. You could nofollow the image and "View Product" links and funnel more PageRank through the much more contextually relevant product name-based text links. Amazing, eh?

So the next time you are considering your options for getting a jump on your competitors in the search results, take a closer look at PageRank sculpting. By strategically adding the "rel=nofollow" attribute to links within your site, you will better direct that precious link juice to the places where it's needed the most.

Bear in mind that PageRank sculpting is an advanced SEO tactic and should be used with care. PageRank sculpting is not a replacement for a well thought out, solid information architecture (IA), so don't rely on PageRank sculpting in lieu of fixing your IA issues.

Despite one vocal detractor, I remain convinced the tactic is completely safe. It's conceivable that, in the future, overuse of the tactic could tag you as a sophisticated SEO and earn your site additional scrutiny.

Happy sculpting!

Note: Want to learn other advanced SEO tactics like this one? The author of this article, Stephan Spencer, will be presenting a MarketingProfs virtual seminar this Thursday, "Advanced Tactics in SEO: Part Art, Part Science," along with fellow search expert Rand Fishkin of SEOmoz. Sign up now.