1000 Forms of Fear is the sixth studio album by Australian singer Sia. It was released on 4 July 2014 by Monkey Puzzle and RCA Records worldwide, and Inertia Records in Australia. Primarily an electropop album, the record also incorporates influences from reggae and hip hop. Lyrically, the record is focused on Sia struggling to deal with drug addiction and a diagnosis of bipolar disorder at the time, later rediagnosed as complex PTSD in 2019.

1000 Forms of Fear received generally favorable reviews from music critics, who praised Sia's vocals as well as the album's lyrical content. The album debuted at number one on the US Billboard 200 with first-week sales of 52,000 copies. The release also charted atop the charts of Australia and Canada, and reached the top five charts of Denmark, New Zealand, Norway, Sweden, Switzerland, and the United Kingdom. As of 26 October 2015, it has been certified gold by the RIAA denoting 500,000 equivalent-album units sold in the United States. As of January 2016, the album has sold 1 million copies worldwide.

The album spawned four singles. Its lead single, "Chandelier", released in March 2014, became a worldwide top-10 single; it also peaked at number eight on the US Billboard Hot 100, becoming the first song by Sia to enter the chart as a lead artist. "Big Girls Cry" was released in June 2014. Sia's solo version of "Elastic Heart", which was originally a collaboration with The Weeknd and Diplo, was released in January 2015, and reached the top 20 of the Hot 100. "Fire Meet Gasoline" was released as the fourth and final single in Germany on 19 June 2015. The official music video for "Chandelier" has been viewed on YouTube more than 2 billion times, and the video for "Elastic Heart" has been viewed more than 1 billion times.

To promote the project, Sia appeared on a number of TV shows, including The Ellen DeGeneres Show and Jimmy Kimmel Live!, where she recruited Maddie Ziegler, who starred in three music videos from the album, as her persona onstage, during 2014 and 2015. 1000 Forms of Fear earned Sia three ARIA Music Awards in 2014 and was listed as one of the best albums of 2014 by several publications, including The Boston Globe and Rolling Stone. The lead single "Chandelier" received four Grammy nominations for Song of the Year, Record of the Year, Best Pop Solo Performance, and Best Music Video.