Any knowledgeable Digital Marketing Agencies knows link building has changed in the last few years, gone are the days of acquiring 1000's of poor quality links Google now class as spam. We primarily deal with SEO and digital marketing companies supplying quality do follow links on natural domains.
With just a hand full of links we can take search terms that are outside the top 100 in Google and take them to first page. Links that not only pass juice but "Trust". A secret metric far more powerful than any other.