Long before Charlotte Free, the of-the-moment fashion model, became known for her brightly colored hair, which ranges from pale to neon pink, women in New York City were dousing their manes in Crayola hues.

The coloring process has not changed much since the days of 1980s punk rockers and 1990s grunge enthusiasts, but the patterns, placement and mood of these "shock locks" have evolved.

Some women are even wearing them to the office, as does Numidas Prasarn, 26, who works at the visitor center at the Brooklyn Public Library. She keeps her purple hair long and simply styled.

"It is a conscious effort to address how I feel every day," Prasarn says of the coordination her coif requires. "Do I feel like going with this color or fighting against it?"

Prasarn's hair is monochromatic, but Sally Hershberger, a celebrity hairstylist with salons in New York and Los Angeles, cites "cascading tips" as one way of incorporating brightness that "feels fresh now".

The trend gained traction after the spring 2010 runway shows and reappeared in the 2011 shows.

Julia Wideman, an assistant manager at the New York City-based Bumble and Bumble salon, whose chestnut hair is lavender and green at the ends, says she was influenced partly by styles shown at the Proenza Schouler show.

It might not be surprising that Wideman, or Dani Stahl, the style director at Nylon magazine, have taken to shock locks. But Olivia Goyrn, a Web content manager at an advertising company in Manhattan, is a less likely candidate.

Before Goyrn, 26, dyed her shoulder-length hair neon pink, she warned her employers and was happily surprised to find that they were fine with her new "do".

"Generally, I try to walk the line between grown-up goth and professional," she says. "So far it's working."

Conscious of the adolescent mood that brightly colored hair projects, many women above drinking age take pains to match it with conservative attire.

"You expect to see somebody who listens to Nirvana and never showers and lives that kind of grungy lifestyle," Wideman says of the impression her hair risks leaving. "I like to do the exact opposite with my clothing. In order to balance it out, I wear cleaner lines and crisper colors, more monochromatic and more neutral."

Andrea Praet, the senior trend director at New York's Stylesight, which collects data on fashion and beauty trends, says: "There is definitely a DIY element, but it's sophisticated" because women are wearing their bright hair with Chanel clothing. "This isn't a flannel-and-torn-everything look," she says.

And while one might expect to see shock locks done in a jagged cut, increasingly they are wound into a chignon, for a whimsical effect that Praet describes as the "twisted lady".

"It's about granny chic," she says.

Tavi Gevinson, a teenage fashion blogger, has had that look with subtle white, violet or blue tones in her hair. "This is the advanced style," Praet says. "It's taking it and doing it in an ironic way. It's really about the style and the attitude when it comes to pulling off these hair trends."

But swagger alone is not enough to pull off bright hair. Whether done in a home bathtub or in a salon, the right technique, which can involve stripping all of the hair's natural color with bleach for maximum saturation, is crucial.

Women fearful of causing damage or just nervous have many noncommittal options, like clay and henna, which are available at health-food stores; Manic Panic's new colored styling gel; and clip-on tracks in Rainbow Brite colors, like those made by Paul's Hair and Beauty World or Sally Beauty.

Brightly colored hair is becoming "more accepted into the mainstream", says Eileen Bellomo, New York founder of Manic Panic. "It's also a low-cost way to feel happy."

Praet agrees. "This isn't like the 90s," she says. "There is a more optimistic undertone to this look."

New York Times