The fashion world’s code word for “make or break” is “the September issue.”

Here are what some of the magazines are offering:

• InStyle celebrates its 15th anniversary with Jennifer Lopez on the cover in a space-age, structured Jil Sander dress. Usher gets kudos for being a “man of style,” beauty products are put to the test and fall trends are dissected with wearibility in mind.

• Amanda Seyfried is the main model for Allure. In an interview, she says, “I do my fair share of judging when I see certain women on the covers of magazines. I think, why is she on the cover?” Allure also differentiates what’s stylish versus merely fashionable whether you’re at the office, hanging out or going to a party.

• Ashley Olsen is on the cover of Marie Claire. She had been on the September cover two years ago and “readers loved it,” gushes Cole. “I like to put people who haven’t done a million other covers. She really had said goodbye to the celebrity lifestyle and is all about fashion now.”

• The bronze, one-shoulder glitter dress worn by Leighton Meister on the cover of Harper’s Bazaar covers many of the seasonal trends. Most unexpected is a spread that celebrates the 40th anniversary of “Sesame Street” by pairing designers with furry creatures: Diane von Furstenberg and Big Bird, for example, and Oscar de la Renta with Oscar the Grouch.

• Jessica Simpson’s Glamour cover photo bears little resemblance to her pictures in the tabloid magazines. Here she looks like the head of the $450-million fashion empire that she is. Inside, there are many pages with service-oriented tips and shopping advice.

• Pamela Fiori, Town & Country’s editor in chief, decided months ago to put Jane Krakowski on the cover, gambling that she’d be nominated for an Emmy Award. The issue reminds recession-weary readers they don’t need new wardrobes, they need key pieces that will prove good investments — alligator pumps, for example.

• Kate Moss is the only professional model with a cover gig — on the front of the fashion-forward W. She models Prada’s fall collection. There’s also an interview with Miuccia Prada, who talks about the effect of the economy on the industry: “When you say ‘commercial’ it shouldn’t be an insult, like something is not beautiful”

• Lucky promises an issue full of shopping strategies, including buying versatile pieces like a military jacket and a leopard-print blouse. Mandy Moore appears for the fourth time on the cover and makes the case for a simple, chic look. “I’m really into simple things I can grab and wear every day,” she says. “I get bored with anything too statement-y.”

• Oprah Winfrey is, as always, on the cover of O, The Oprah Magazine, this time with a sly grin promising a wake-up call for your wardrobe. Inside, reality TV stars model the trends.

• The little black dress comes alive in a corset shape on Kristen Bell on the cover of Cosmopolitan. The sexy fall styles? Studded shoe booties, a bomber jacket, punk-glam jewelry — and the editors say guys like headbands.