Search engine marketing, or SEM, is a form of Internet marketing that seeks to promote websites by increasing their visibility in search engine result pages (SERPs) through the use of search engine optimization, paid placement, contextual advertising, and paid inclusion.
In 2008, North American advertisers spent US$13.5 billion on search engine marketing. The largest SEM vendors are Google AdWords, Yahoo! Search Marketing and Microsoft adCenter. As of 2006, SEM was growing much faster than traditional advertising and even other channels of online marketing.Because of the complex technology, a secondary "search marketing agency" market has evolved. Some marketers have difficulty understanding the intricacies of search engine marketing and choose to rely on third party agencies to manage their search marketing.
As the number of sites on the Web increased in the mid-to-late 90s, search engines started appearing to help people find information quickly. Search engines developed business models to finance their services, such as pay per click programs offered by Open Text in 1996 and then Goto.com in 1998. Goto.com later changed its name to Overture in 2001, and was purchased by Yahoo! in 2003, and now offers paid search opportunities for advertisers through Yahoo! Search Marketing. Google also began to offer advertisements on search results pages in 2000 through the Google AdWords program. By 2007, pay-per-click programs proved to be primary money-makers for search engines. In a market dominated by Google, in 2009 Yahoo! and Microsoft announced the intention to forge an alliance. The Yahoo! & Microsoft Search Alliance eventually received approval from regulators in the US and Europe in February 2010.
Search engine optimization consultants expanded their offerings to help businesses learn about and use the advertising opportunities offered by search engines, and new agencies focusing primarily upon marketing and advertising through search engines emerged. The term "Search Engine Marketing" was proposed by Danny Sullivan in 2001 to cover the spectrum of activities involved in performing SEO, managing paid listings at the search engines, submitting sites to directories, and developing online marketing strategies for businesses, organizations, and individuals.
Some of the latest theoretical advances include Search Engine Marketing Management (SEMM). SEMM relates to activities including SEO but focuses on return on investment (ROI) management instead of relevant traffic building (as is the case of mainstream SEO). SEMM also integrates organic SEO, trying to achieve top ranking without using paid means of achieving top in search engines, and PayPerClick SEO. For example some of the attention is placed on the web page layout design and how content and information is displayed to the website visitor.
Paid search advertising has not been without controversy, and the issue of how search engines present advertising on their search result pages has been the target of a series of studies and reports by Consumer Reports WebWatch. The Federal Trade Commission (FTC) also issued a letter in 2002 about the importance of disclosure of paid advertising on search engines, in response to a complaint from Commercial Alert, a consumer advocacy group with ties to Ralph Nader.
Vested interests appear to use the expression SEM to mean exclusively Pay per click advertising to the extent that the wider advertising and marketing community have accepted this narrow definition. Such usage excludes the wider search marketing community that is engaged in other forms of SEM such as Search Engine Optimization and Search Retargeting.
Another ethical controversy associated with search marketing has been the issue of trademark infringement. The debate as to whether third parties should have the right to bid on their competitors' brand names has been underway for years. In 2009 Google changed their policy, which formerly prohibited these tactics, allowing 3rd parties to bid on branded terms as long as their landing page in fact provides information on the trademarked term. Though the policy has been changed this continues to be a source of heated debate.