Some agencies still focus on building links, but I’m unsure I’d call which a strategy. The great link-focused agencies will often have a bag of tactics/tricks they love. These tactics are proprietary, meaning it’s difficult to find them all spelled out on Quora.
That being said, there are some great tactics shared on regularly, and you’ll find lots of interesting stuff looking around on that site also (a lot of which is free).
However, in terms of a strategy, professional link building plays second fiddle. Links aren’t the be-all-end-each one of web marketing – you require them to have success, however you also require an excellent social media presence, good content, website that converts, etc.
I think, link-building suits a better online content and PR strategy.
At my agency, we give attention to a niche market (auto parts), which allows us to both cultivate content expertise (all of my content creators are car nerds) and cultivate relationships with industry media (I’ve got a decent list of automotive journalists and bloggers I will get in touch with and expect a response). Our strategy:
Create content we hope auto enthusiasts will delight in (and our company of car nerds makes us somewhat successful at this)
Contact the top journalists/bloggers from the automotive niche (whom we realize, or at least know via email) and “pitch” them our content
If/once the content resonates with all the blogger/journalist, we get a mention of the client’s manufacturer, and almost always the link
The hyperlinks are editorial and range from top quality sites, therefore we have nothing to fear from my efforts. It’s 100% “white hat,” which you can’t always say about link building. The manufacturer name mentions put our clients facing thousands (or tens of thousands) of automotive enthusiasts. I don’t actually know 40dexppky the ROI on these mentions is, but it really can’t be bad.
…In addition to, we’ve got a cool part of content about the client’s site that could generate search and social networking traffic/interest for many years.
Our “trick” is definitely an industry and niche focus. It’s difficult to create content that really “pops” if you don’t have knowledge of-house, in addition to that it’s difficult to determine who the most notable bloggers and journalists happen to be in a distinct segment without having done any some are employed in that niche for a few years.