PARIS — “It’s not merely a dress for less — it was more a laboratory for me to understand things,” said Alber Elbaz of Lanvin about his 30-piece capsule collection for H&M, to be presented this week, that will go on sale Nov. 23.

The designer — the latest in Hennes & Mauritz’s lineup of high/low collaborations that started with Karl Lagerfeld in 2004 and has included Stella McCartney, Comme des Garçons and Victor & Rolf — has brought his kooky femininity to the Swedish “fast fashion” chain.

The aim is to offer to a far greater audience Lanvin’s wit and fantasy, using bold prints, playful ruffles and vivid colors like sunshine yellow, alongside imaginative creations in black. In other words, to bring the haute style that Mr. Elbaz sends out on the Paris runways to a wider world.

“But I was thinking about the definition of luxury and about H&M, and I wanted them to go up rather than Lanvin to go down,” says the designer of what he calls “an interesting exercise in high street and high fashion.”