By 1997 search engines recognized that some webmasters were making efforts to rank well in their search engines, and even manipulating the page rankings in search results. Early search engines, such as Infoseek, adjusted their algorithms to prevent webmasters from manipulating rankings by stuffing pages with excessive or irrelevant keywords.

Due to the high marketing value of targeted search results, there is potential for an adversarial relationship between search engines and SEOs. In 2005, an annual conference, AIRWeb, Adversarial Information Retrieval on the Web, was created to discuss and minimize the damaging effects of aggressive web content providers.

SEO companies that employ overly aggressive techniques can get their client websites banned from the search results. In 2005, the Wall Street Journal profiled a company, Traffic Power, that allegedly used high-risk techniques and failed to disclose those risks to its clients. Wired reported the same company sued blogger Aaron Wall for writing about the ban. Google’s Matt Cutts later confirmed that Google did in fact ban Traffic Power and some of its clients.

Some search engines have also reached out to the SEO industry, and are frequent sponsors and guests at SEO conferences and seminars. In fact, with the advent of paid inclusion, some search engines now have a vested interest in the health of the optimization community. Major search engines provide information and guidelines to help with site optimization. Google has a Sitemaps program to help webmasters learn if Google is having any problems indexing their website and also provides data on Google traffic to the website. Yahoo! Site Explorer provides a way for webmasters to submit URLs, determine how many pages are in the Yahoo! index and view link information.