A Guide to Sia's Most Major 'This Is Acting' Collaborations: Kanye West, Adele and More

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It wouldn't be a Sia project with an A-list collaboration.

The singer unveiled her highly-anticipated new album, This Is Acting, on Friday, and there are more than a few high-profile names in the liner notes. Of course, this should come as a surprise to no one. Sia made a name for herself penning hits like "Diamonds" for Rihanna, "Perfume" for Britney Spears, "Pretty Hurts" for Beyonce, "Invincible" for Kelly Clarkson, and "Flashlight" (with Sam Smith!) for Jessie J -- among others.

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Her latest collection features songs written initially for other artists but never before released. "I feel like they're hits, but nobody wanted them," Sia told Rolling Stone of the album. "So I thought, 'Let's see, as an experiment, if I'm right.'"

Sia re-teamed with several of her frequent collaborators -- including Chris Braide, Greg Kurstin and Jesse Shatkin -- on this project, but there are plenty more epic (and surprising!) collabs worth noticing. We're breaking down five This Is Acting tracks you'll want to pay extra close attention to.

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1. "Alive"

Co-written by Adele

As was widely reported before its release, "Alive" was first written for Adele's 25, but didn't make the final cut.

2. "Reaper"

Co-written, co-produced by Kanye West

Sia's vocals are featured on West's Waves track, "Wolves" -- perhaps "Reaper" was born from the same studio session?

3. "House on Fire"

Co-written, co-produced by Jack Antonoff

Last year, Antonoff recruited Sia to sing on the all-female covers version of Bleachers' Strange Desire. Clearly, the partnership was a match made in musical heaven: Their new song is relentlessly catchy, to say the least. 

4. "Sweet Design"

Co-written by the "Thong Song" team

While it's nearly impossible to decipher all of Sia's rapid-fire lyrics, "Sweet Design" features the unmistakable sample of Sisqo's 1999 hit, "Thong Song." (Nope, we're not kidding -- and it's pretty glorious.)

5. "Footprints"

Produced, co-written by T-Minus

Known primarily for his work with rap artists (Drake, Lil Wayne, Nicki Minaj, Kendrick Lamar, Ludacris and Big Sean among them) producer T-Minus goes decidedly pop on this piano-heavy anthem.

Which This Is Acting track is your favorite? Hit the comments with your picks!

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