YouGov is an international Internet-based market research firm, headquartered in the UK, with operations in Europe, North America, the Middle East and Asia-Pacific. It has no known connection with the UK government. Stephan Shakespeare, the firm's CEO as of 2017[update], once stood as a Conservative candidate for Colchester; he was also a Conservative Party pollster.
Shakespeare has been YouGov’s Chief Executive Officer since 2010. Roger Parry has been YouGov’s Chairman since 2007. Political commentator Peter Kellner was YouGov’s President until he stepped down in 2016.
YouGov specialises in market research through online methods. The company’s methodology involves obtaining responses from an invited group of Internet users, and then weighting these responses in line with demographic information. It draws these demographically-representative samples from a panel of 5 million people worldwide including over 800,000 people in the UK. As YouGov's online methods use no field-force, its costs are lower than some face-to-face or telephone methods.
YouGov has claimed that its opinion polls are most accurate when compared to its competitors and in particular that its online methodology is more accurate than traditional polling methods. Critics have argued that, as not all of the public have access to the Internet, online samples cannot accurately reflect the views of the population as a whole. YouGov counters that they have a representative panel and they are able to weight their data appropriately to reflect the national audience that they are aiming to poll.
Opinion poll analysis website FiveThirtyEight assigns YouGov a grade of B (no. 81 of 372 pollsters), calling 93 percent of races correctly, and with a slight bias towards the Democratic Party in United States elections. 
In May 2017 it predicted, on the basis of its new polling model, that the result of the United Kingdom general election, 2017 would be a hung parliament. This was described as "brave" but turned out to be right.
In 2006 YouGov began expanding outside the UK through acquisitions and acquired Dubai-based research firm Siraj for $1.2 million plus an eventual earn out of $600,000. In 2007 they added Palo Alto, CA based US research firm Polimetrix for approximately $17 million, Scandinavian firm Zapera for $8 million and German firm Psychonomics for $20 million. In 2009 and 2010, YouGov expanded its US operations with two acquisitions; first buying Princeton, NJ research firm Clear Horizons for $600,000 plus an earn out of $2.7 million, then Connecticut-based research firm Harrison Group for $6 million with a $7 million earnout. In 2011, YouGov acquired Portland, OR-based firm Definitive Insights for $1 million with a potential $2 million earn out. In 2011, YouGov made its first organic expansion by opening an office in Paris, France. In January 2014, YouGov entered the Asia Pacific region with the acquisition of Decision Fuel for an estimated consideration of approximately £5 million.