When Sony tapped Valerie Van Galder as president of domestic marketing for Columbia TriStar Motion Picture Group in late 2005, it was a big step up.

The marketing maven, who cut her teeth on specialty fare at Fox Searchlight, had been focusing on reviving Sony’s TriStar label and marketing genre fare from its Screen Gems group.

The volume — and the stakes — were much higher when she gained responsibility for Columbia fare. And it didn’t help that the studio had just gone through an off year.

Van Galder stepped up to the challenge with alacrity, helping the studio drive hits like “The Da Vinci Code” and “Casino Royale” to a record $1.7 billion year at the box office and No. 1 ranking in market share.

This summer, the studio started out with a bang with “Spider-Man 3” ($886 million worldwide as of July 23), and is expected to cross $1 billion in 2007 — the sixth consecutive year in a row, a feat unmatched by any other studio.

Small wonder Ad Age recently named Van Galder entertainment marketer of the year.

Van Galder says the scope of her new responsibility — and having to manage a big staff — was more daunting than the size of the movie budgets in Columbia’s pipeline.

“Movies big or small all require a lot of attention and work,” Van Galder says. “The biggest challenge the first year was the enormous slate,” she explains. “Once I got through that, I felt I could do anything.”

Her latest challenge is harnessing the power of the Internet with viral marketing schemes on sites like YouTube.

“The Internet has really changed everything dramatically,” Van Galder says. “Everyone is trying to figure out how to manage it.”

Vocation: Sony’s chief domestic marketer

Recent breakthrough: Made the leap to big-budget films without breaking a sweat.

Role model: “My mom. She did it all.”

Career mantra: “Same as my life mantra: Do unto others. Try to be fair and honest.”

What’s next: “Superbad” — “From the brilliant, creative mind of (producer) Judd Apatow.”