Search engine marketing (SEM) is a form of Internet marketing that involves the promotion of websites by increasing their visibility in search engine results pages (SERPs) primarily through paid advertising.

SEM is the wider discipline that incorporates SEO. SEM includes both paid search results (using tools like Google Adwords or Bing Ads, formerly known as Microsoft adCenter) and organic search results (SEO).

SEM uses paid advertising with AdWords or Bing Ads, pay per click (particularly beneficial for local providers as it enables potential consumers to contact a company directly with one click), article submissions, advertising and making sure SEO has been done.

A keyword analysis is performed for both SEO and SEM, but not necessarily at the same time. SEM and SEO both need to be monitored and updated frequently to reflect evolving best practices.