A model presents a creation from the Badgley Mischka Spring 2010 collection during New York Fashion Week, September 15, 2009.

NEW YORK - Financial crises and war have long fostered dramatic innovations in fashion, and today's times are no different, according to Nina Garcia, author of the new book "The Style Strategy."

The "recessionista" has replaced the "fashionista" in this economy, marking a "pivotal moment that will create a lot of changes" in how consumers shop, said Garcia, fashion director at Marie Claire magazine and a judge on the hit television show "Project Runway."

The style guide, Garcia's third book to be published by Harper Collins, looks at how savvy shoppers have adjusted to this moment by learning to not shop on a whim.

To aid in teaching the science, she peppers the book with historical reminders of how fashion has found a way to adapt to hard times.

In World War II, leather shortages forced shoemakers to switch to cork and wood soles, giving birth to platform shoes. With fabric in short supply, shirt cuffs were deemed wasteful and eventually went out of style.

During the Great Depression, flour sacks caught on as an inexpensive fabric for dresses, so much so that flour companies began designing distinctive prints to feed the trend.

"When we have a crisis like this, I think everybody has to find better, creative ways to work," Garcia told Reuters. "It goes beyond just designing clothes. It's how we sell them, how we buy them -- it's everything."

Garcia suggests that this time, the most pivotal innovations will not be so material.

FASHION BECOMING 'A LOT MORE SELF-AWARE'

Garcia said she could not imagine a return to frivolity in the industry.

"There's a consciousness in fashion that wasn't there before," she said, citing greater attention to consumer personal finances, fashion manufacturers' costs and the growing green movement. "We're all becoming a lot more self-aware."

But in her book, Garcia said her goal is to show that such changes do not have to dampen the pleasures of shopping. Instead, they call for a re-evaluation of priorities, she said.

"Have fun! But do not do so much impulse buying. Think about it, have a strategy," she said.

Her cardinal rule is to know exactly what is in one's wardrobe before a shopping trip, to separate needs from wants.

To Garcia, the biggest changes in the fashion industry stem from consumers who have more access to a wider range of looks at a wider range in prices, thanks to large stores such as Target and H&M that sell stylish inexpensive clothing and to shopping outlets online.

Big luxury companies will become more specialized and offer more unique items, she predicted, adding, "It's not going to be at the same level as it was."