The day after every Mormon Tabernacle Choir Christmas concert, Mack Wilberg wakes up planning the bill for the next year. "That's a good thing," the choir's music director said, because it means that show was a success and he wants to make the next year's concert even better.

Wilberg doesn't work alone on the venture, of course. "There's an army behind the scenes, making sure that things happen the right way," he said of the scores of technicians, support staff and volunteers who help produce the show.

That army is marching happily to the beat of holiday music, much of it composed or arranged by Wilberg, for the show at the LDS Conference Center, headlined by singer Natalie Cole and author David McCullough. Other performers include the Orchestra at Temple Square, the Bells on Temple Square, more than 100 dancers and some surprise guests.

Wilberg is guarded about revealing details for this year's show. "Let's just say I've done some new things that will be filled with surprises," he said.

One secret squeezed out of Carol Iwasaki, the show's choreographer and a University of Utah ballet professor, is that the concert's processional will include original music composed by Wilberg containing hints of a familiar Christmas carol. "I tried to interpret the music's theme, which is a message of coming," Iwasaki said.

Dancers, who are mostly young amateurs and local dance instructors, were auditioned in September. Some drive from as far away as Idaho for rehearsals. "This is probably the highlight of my life," said Iwasaki, who is marking her fifth year choreographing the show. "It's an amazing place to work and great to be valued."

Performing in the cavernous Conference Center poses unique challenges. "If something goes wrong in rehearsal, it takes five minutes to reset everyone at the starting point," Iwasaki said.

Wilberg also takes the hall's size into account when arranging and composing his music. "There almost has to be a pageantlike quality to most everything that's done in the Conference Center to have any kind of impact," Wilberg said. "It's a wonderful hall. It's just big."

According to Conference Center ticket officials, 1.2 million tickets were requested, while 84,000 free tickets were distributed through a random computerized system for four shows.

The stress of trying to make everything perfect for the audience keeps Wilberg busy. He's now in his second year directing the choir, although he's been working to produce the Christmas concerts for 10 years. "My life is anything but boring," said Wilberg, and he's not complaining.

When this year's concert wraps up, Wilberg expects he'll wake up eager to began planning his second decade of Christmas extravaganzas.