Danny Sullivan is California-based technologist, journalist and an entrepreneur. He was the Chief Content Officer at Third Door Media, and co-founded Search Engine Land, an industry publication that covers news and information about search engines, and search marketing, SEO and SEM topics. Third Door Media also produces Marketing Land, a sister website that covers broader digital marketing topics including social media, display advertising, email marketing, analytics, mobile, and marketing technology. Search Engine Land and Marketing Land are owned by Third Door Media, of which Danny Sullivan was partner and chief content officer. He retired from his position as Chief Content Officer at Third Door Media in June 2017.
In October 2017, Sullivan announced he will be joining Google as an adviser at the search division of the company. Danny is Google's public Search Liaison: helping people better understand search and Google better hear public feedback. 
Danny was one of the 50 marketing influencers, according to Entrepreneur, in 2015.
Sullivan was born in 1965 and raised in California. He graduated from the University of California, Irvine, and was a reporter for the Los Angeles Times and The Orange County Register. Danny helped found Maximized Online with programmer Ken Spreitzer. Later, he married Lorna Harris, and lived for several years in Chitterne, a small village in England. They have two sons. The family moved to Newport Beach, California. Sullivan popularized the term Search Engine Marketing within an article he published on Search Engine Watch although he does not take credit for coining the term.
Sullivan started Search Engine Watch in June 1997 after he posted research about search engines, called A Webmaster's Guide To Search Engines, in April 1996. Search Engine Watch was a website with tips on how to get good search engine results. Shortly after beginning in November that year, he sold it for an undisclosed amount to MecklerMedia (now Jupitermedia). He stayed on to maintain the site, and be the editor-in-chief. In 2006, it was sold to Incisive Media for $43 million. Search Engine Watch was considered by Matt Cutts of Google as "must reading", and Tim Mayer of Yahoo! as the "most authoritative source on search".
He also staged the Search Engine Strategies conference six times each year, attracting 1,500 to 6,000 attendees each time. On 29 August 2006, Sullivan announced he would be leaving Search Engine Watch on 30 November 2006. He later came to an agreement with Jupitermedia to continue participating in SES through 2007.
Search Engine Land is a news website that covers search engine marketing and search engine optimization. One of the well-known blogs which shares information about keyword research, trends in search marketing (SEM), paid search advertising (PPC) and search engine optimization (SEO) as well as analysis, advice, tips, tactics and how-to guides for search marketing. It was founded in 2006 by Sullivan after he left Search Engine Watch. Search Engine Land stories have been cited numerous times by other media outlets.