Playbill.com has put together a collection of performances (of various songs) by Houston, Jennifer Hudson, and Tony Award winner Heather Headley, who stars in the London production of the new musical.

Heather Headley - "I Have Nothing."

Heather Headley – "So Emotional."

Heather Headley – "I Will Always Love You."

Heather Headley – "Where Do Broken Hearts Go."

Heather Headley sings Elton John's "Your Song."

Heather Headley singing "Somewhere Over The Rainbow."

Jennifer Hudson tributes Whitney Houston with "I Will Always Love You."

Jennifer Hudson tributes Whitney Houston with a special medley.

A live performance of the pop duet "I Know Him So Well" with Houston and her mother Cissy.

You get three unreal performances for the price of one in this thunderous medley of "I Loves You Porgy," "And I'm Telling You I'm Not Going" and "I Have Nothing."

Jekyll & Hyde and Bonnie & Clyde composer Frank Wildhorn wrote the hit "Where Do Broken Hearts Go?" for Houston's 1988 album "Whitney." Here's a live performance during a concert for Nelson Mandela.

A beautiful audio of Houston offering a medley of Gershwin classics, including "I Loves You Porgy" and "Summertime."

The official video of "When You Believe," a duet with Mariah Carey from the animated film "The Prince of Egypt." The film features a score by Academy Award-winning Wicked composer Stephen Schwartz.

An impressive early performance by Whitney singing "I Am Changing" from Dreamgirls during an Arista anniversary concert.

Dolly Parton penned the tender song "I Will Always Love You," first featured in the film of "The Best Little Whorehouse in Texas," which got a pop-ballad make-over for the film "The Bodyguard." Here is Whitney's performance at the Grammy Awards.

Houston as the Fairy Godmother in the Wonderful World of Disney remake of Rodgers and Hammerstein's "Cinderella." Here is her high-flying, pop-influenced rendition of "Impossible."

Knocking out "Home" from The Wiz on "The Merv Griffin Show."