After conducting decades’ worth of holiday pops concerts, Michael Krajewski appreciates the concept of keeping things fresh. Making his debut with the Chicago Symphony Orchestra, conducting this season’s edition of “Merry, Merry Chicago!,” is certainly one way to do it.

“It’s one of the finest orchestras in the world,” Krajewski said by phone recently from Orlando, Fla., where he lives when he’s not on the road leading symphonic pops concerts. “I’ve been doing Christmas concerts for 30 years, but this is going to be fresh and enjoyable for me, because it’s a new orchestra and one of the greatest there is.”

A holiday pops concert has to be both familiar and novel. Many families make “Merry, Merry Chicago!” (running Dec. 14-23) part of their December ritual, and some elements have to remain the same. But concertgoers need something different to look forward to as well, so the symphony tries to program pieces that haven’t been heard for a few years. “It can’t be the same old same old,” Krajewski said. “We have to find really good arrangements of whatever Christmas songs we’re doing that sound fresh and alive, with a different perspective.” Good arrangements, he said, will show off the orchestra’s abilities and be “challenging and gratifying for musicians of their caliber” — but not too difficult to put together quickly.

For more variety, Krajewski has programmed several pieces for orchestra only, with no Christmas connection or a very slender one. Bizet’s Farandole from L’arlésienne, for instance, takes its tune from the French March of the Three Kings, and Johann Strauss’ Thunder and Lightning Polka, in its original German title, is Donner und Blitzen.

Another way to introduce something new is with a piece composed last year: in this case, On Christmas Day, a loose arrangement of I Saw Three Ships, written by Steve Amundson for St. Olaf College in Minnesota. In the opening spot on the program, “it’ll sound like a new piece,” Krajewski said, “but you’ll hear references to the song.”

This season, the solo vocalist is singer-songwriter Storm Large, whom Krajewski has worked with in other orchestras. In addition to several beloved holiday carols, Large also will perform two Christmas-related songs she composed herself, keeping the holiday canon alive and growing.

The choral element will be provided by the Young Naperville Singers, a children’s choir from Chicago’s western suburbs. Its choristers have been rehearsing their parts since the school year began, but Krajewski will get only a few rehearsals with the full assembled forces. “It’s not a problem with an orchestra like this,” he said. “But it’s cool to be there and have everything come together.”

Pacing a program, moving from one mood to another or one group of artists to another, is a skill of its own, and much more art than science, Krajewski said. “Sometimes you end big, bright and happy, and sometimes you end with something sentimental. In this case, we’re going big” — the full forces of orchestra, chorus and soloist combining on Joy to the World and O Come, All Ye Faithful.

Krajewski’s pops career goes back 30 years, to his time as an assistant conductor with the Detroit Symphony. Like anyone in that role, he led a great many concerts where he was expected to talk to the audience as well as conduct — children’s concerts, educational concerts and pops. His work got noticed, and he received more and more offers to guest conduct other orchestras’ pops concerts until he decided to do it exclusively.

“His wry wit, as spontaneous as a stand-up comedian’s, emerged to amuse the audience,” Charles Ward wrote recently in the Houston Chronicle. “He is as effective and entertaining a communicator in music as he is in words.”

“There’s kind of a mystique about the conductor, or just about going to a symphony concert,” Krajewski said. Talking, telling jokes and establishing a welcoming atmosphere “breaks down the barrier immediately. If you do it correctly, the audience relates to you.”