In 2007, he won the Tony Award for Best Lighting Design in a Play for his work on The Coast of Utopia (Part 2 - Shipwreck).
He has been nominated for the Tony Award for Best Lighting Design 11 times and won once for The Coast of Utopia (Part 2 - Shipwreck) in 2011.
His nominations have included nods for Merchant of Venice (2011), Dirty Rotten Scoundrels (2005), Wicked (2004), Hairspray (2003), and The Adventures of Tom Sawyer (2001).
In 2013, Posner achieved a near-sweep of the nominations for the Tony Award for Best Lighting Design of a Musical, garnering nods in three of the four eligible slots (for Kinky Boots, Pippin, and Rodgers + Hammerstein's Cinderella), though he lost to Matilda The Musical.
Posner was educated at SUNY Purchase, where Brian MacDevitt also attended.