While she was studying at the University of Edinburgh, Kaiser took time off to work on Barack Obama's media team during his presidential campaign in 2007. She also worked for Amnesty International as a lobbyist appealing for an end to crimes against humanity. Between February 2015 and January 2018, Kaiser worked full-time for the SCL Group, the parent company of Cambridge Analytica, as director of business development. During her time at Cambridge Analytica, Kaiser worked under senior management, including CEO Alexander Nix. Following the Facebook–Cambridge Analytica data scandal, Kaiser fled to Thailand. She later testified before the British Parliament about Cambridge Analytica and privacy threats posed by Facebook. In April 2018, Kaiser started a Facebook campaign appealing for transparency, called #OwnYourData. Kaiser is one of the subjects of the Netflix documentary The Great Hack, talking about her work with Cambridge Analytica. The documentary provides details about how Cambridge Analytica used data brokers and an online app to accumulate information on tens of millions of Facebook users, gathering data on a massive scale. Kaiser's memoir, Targeted: The Cambridge Analytica Whistleblower's Inside Story of How Big Data, Trump, and Facebook Broke Democracy and How It Can Happen Again, was published by Harper in October 2019. The book details how companies are illegally using data to influence people’s choices. In an interview with the BBC, Kaiser said she wanted Facebook to ban political advertising. In June 2019, Kaiser was appointed to the advisory board of Phunware, a tech company that collects the smartphone location and user data of potential voters for the Trump 2020 Campaign On New Year’s Day 2020, Kaiser began to release internal documents from Cambridge Analytica links to material on elections in Brazil, Kenya and Malaysia. In an online interview with Philippine media outletRappler on July 15, 2020, Kaiser revealed that former Senator Ferdinand "Bongbong" Marcos Jr, son of the late dictator Ferdinand Marcos Sr, had approached Cambridge Analytica with a request to do a "rebranding" of the family's image. She described the efforts of the Marcos family to rebrand their family image as an example of historical revisionism in a data-driven and scientific way. This request was said to have brought up heavy debate among the staff at Cambridge Analytica, but was nevertheless accepted by CEO Alexander Nix, as it was a financial opportunity. Rappler requested a comment from Marcos' spokesperson Vic Rodriguez, who replied on Thursday morning, denying the allegations brought up by Kaiser. Rodriguez branded the report as "patently fake, false, and misleading", denying that his party had never heard of Cambridge Analytica until their data breach scandal. He also accused Rappler of creating a "marketing ploy" to boost support towards the news outlet and stated that Marcos is considering legal options against Rappler for the report.