Prior to bringing Next to Normal to Broadway, Yorkey was affiliated with Village Theatre in Issaquah, where he began as a KidStage student and eventually progressed to a six-year tenure as associate artistic director. Five musicals written by Yorkey—Funny Pages (1993), Making Tracks (2002), The Wedding Banquet (2003), Play it by Heart (2005), and A Perfect Fall (2007)—were staged there.
Next to Normal began as a ten-minute-long piece called Feeling Electric, which recent college graduates Yorkey and Kitt wrote as a final project for the BMI Musical Theatre Workshop at the end of the 1990s. Their inspiration was a segment about electroconvulsive therapy Yorkey saw on Dateline NBC. Yorkey has observed it's "exponentially harder to write an original musical. Musicals that go wrong can be ridiculous because it's a ridiculous art form. People bursting into song can be ridiculous. But musicals that go right can be sublime."Next to Normal won the annual Pulitzer Prize for Drama in 2010, citing "a powerful rock musical that grapples with mental illness in a suburban family and expands the scope of subject matter for musicals." It also won the 2009 Tony Award for Best Original Score and was nominated for the Tony Award for Best Book of a Musical.
Yorkey is currently writing the original musical SCORE!, with Robert Downey, Jr. attached to star, which is set up at Warner Bros. with Anonymous Content and Team Downey producing. His screenplay Love Undercover is set up at Overture Films with Pandemonium producing. He also scripted Sluts for Lionsgate Films and co-created the series The Bears Next Door for the Logo network. Brian’s first feature film pitch, Time After Time, sold in a bidding war for high six figures to Universal Pictures. It is now fast tracked at Lionsgate/Summit with Brad Buecker (GLEE, AMERICAN HORROR STORY) directing. He is also working with the legendary English singer Sting on a musical theatrical work based on The Soul Cages.
In August 2010, Tom Kitt and Yorkey's musical In Your Eyes was workshopped at the Village Theatre's Festival of New Musicals in Issaquah, Washington (they also workshopped Feeling Electric there as well). The show is about "The students of Lakeshore High School are sent into a full-blown lock down (not to mention a flood of animosity, fear, and insecurity) when a plot of gun violence is suspected. As a group of unsupervised students attempts to make sense of the chaos, they end up learning more about themselves and their classmates—from the troubled rocker spitting lyrics, to the sarcastic fashionista pointing fingers from her pedestal."