If you’ve ever found yourself envious by Emma Stone‘s red-carpet updos, Olivia Wilde‘s boho waves, Cara Delevingne‘s tousled bends, or Zoe Saldana‘s polished blowouts, you have Mara Roszak to thank for that. The Los Angeles-based stylist and Laurel Canyon native is a master of arguably the most coveted aesthetic in hair: beachy, artfully disheveled California cool. Star-studded as her roster may be, Roszak also takes regular clients (granted, those who can spring for $400 haircuts) out of Mare Salon in West Hollywood, where she’s a partner and co-owner. Her day-to-day interactions there give her insight into something her A-list appointments don’t: what women who don’t have access to a professional every time they step out want to know about styling their hair. Today, armed with that knowledge and over 15 years of industry experience, Roszak brings her learnings to the masses with RŌZ Santa Lucia Styling Oil, a product meant to simplify overcomplicated routines by working for all hair types. “I talk to women every day who want to understand what products to use and how to use them,” Roszak tells Refinery29. “It’s really overwhelming and generally hard to find products that you love.” Hair oil, she explains, was a natural choice for her first launch, which she’s been working on for two-and-a-half years. “Before I do a client for an awards show or anything, I use hair oil first and style everything on top,” she says. “It helps to smooth, to speed up the drying process, to protect the hair from heat — and if you don’t want to style your hair, it’s really the only product you need for a little bit of definition and shine.” In addition to its versatility, Roszak says there’s one crucial objective she had in mind when formulating the Santa Lucia Styling Oil. “I see so many different types of hair, and I wanted to make sure we weren’t excluding anybody here,” she says. “I specifically formulated this to work on every head of hair, from the most textured or dry to women with fine hair who are fearful of using oil typically.” Olive, sunflower, argan, jojoba, and safflower oils make for a texture that’s deceptively lightweight yet buildable. “None of the ingredients are heavy oils,” Roszak reiterates. “Emma’s hair can take it; I’m dropping off more for Cara today. I always say to start with two pumps, but you can’t use too much as long as you’re not pouring it into the palm of your hand.” Even the bottle — with its frosted-glass finish, seafoam-green cap, and floral motif — looks like something an especially chic mermaid might reach for to seal split ends or smooth down frizz. The fragrance, too, is transportive, a quick olfactory trip to the Golden State coast with notes of jasmine, vetiver, and musk. But creating a formula that looks good, smells good, and works well still isn’t quite enough for Roszak: There’s a narrative she’s setting out to reframe with RŌZ. “The messaging on beauty products is often so negative, and I think that has played such a role is how we talk about ourselves,” Roszak says. “I hear these very negative relationships women have to their hair, and it’s because we’re conditioned to see it as something that needs to be fixed. Sure, maybe depending on how much you color or use heat, there are ways it can be improved to bring back that natural beauty. We’re unique, and everybody’s hair is different. I want to create a positive experience, and have these conversations that change the language we use about our hair and ourselves.” At Refinery29, we’re here to help you navigate this overwhelming world of stuff. All of our market picks are independently selected and curated by the editorial team. If you buy something we link to on our site, Refinery29 may earn commission. Like what you see? How about some more R29 goodness, right here?