Two months into preparing an album with an extensive guest list, actor Aaron Lazar had one question: What have we done? “The costs are rising and we’ve got this amazing roster of artists, their managers and their press representatives to deal with,” he says. “It became this really, really epic project. But there was no turning back at that point.

” The result, “Impossible Dream,” features a who’s who of Broadway singing a host of inspirational songs with Lazar. A portion of the proceeds will benefit the ALS Network – something Lazar knows a little something about. Diagnosed more than two years ago with amyotrophic lateral sclerosis, a neurodegenerative disorder, Lazar has been a vocal advocate for others dealing with the disease.

In addition to speaking around the country about his journey, he decided it could get more attention with a “We Are the World”-like project. Aaron Lazar records a song for "Impossible Dream," a new album of duets and group songs. “The Impossible Dream,” a number from “Man of La Mancha” seemed like a natural, since it addressed Lazar’s life for the last few years.

“We got into the studio and I was like, ‘Hold on. Why am I doing this? I don’t need to hear myself sing this song again,’” so he decided to break it into a series of performances and a huge chorus. The result is one of those stirring anthems that includes everyone from Kristin Chenoweth to Josh Groban to Lin-Manuel Miranda.

“From a logistical perspe.