2015 has been a great year for startups. As technology becomes more and more ubiquitous, there are an increasing number of unicorns, companies valued at $1 billion or more. This year, only 39 companies in the world have achieved such a coveted status, or .07 percent of all venture-backed consumer startups. And several of those unicorn companies have been founded, headed, and shaped by women. Co-founder of finance firm KKR Henry Kravis acknowledges that taking a company public is very risky, but some of those women that have done it and reaped the rewards offer great insights about their experiences.

Alexandra Wilkis-Wilson.

A co-founder of Gilt Groupe, an online shopping destination that offers discounts on luxury and high-end items, Wilkis-Wilson says that she never looks at anything as if it is half-empty. “I usually don’t take no for an answer,” she says. A graduate of Harvard Business School who speaks multiple romance languages, Wilkis-Wilson says that working at Louis Vuitton taught her that she could sell anything.

Holly Liu.

Liu is the co-founder of Kabam, a company that creates enormous multiplayer and social media games. Under her direction, the company has frown from $0 to $400 million, finally reaching that gilded unicorn status in 2014. She believes that culture plays a necessary part in creating effective companies because “a global culture helps you to succeed.” She also believes that success is “95 percent executive and 5 percent idea.”

Julia Hartz.

Hartz believes in the power of communication and the value of small teams, or at least teams that feel small and intimate. The co-founder of Eventbrite, a site that lets people find or create events, says that her company prides itself on “having built a culture based off of transparency and real-time communication…We hold weekly sessions called ‘Hearts to Hartz’ where we give business updates, review our key company metrics, share exciting news from the teams, and answer any questions we may have.”

Adi Tatarko.

Now valued at $2.3 billion, Tatarko’s Houzz allows users to shop photo galleries of people doing renovations on their homes. Each month the company draws 25 million visitors to its site, which is more traffic than the big retailers like Nordstrom get. The site is majorly cool: users can browse endless galleries for photos of their dream kitchen and click a link to buy the products they see. Both Tatarko and her husband are immigrants from Israel, and she makes her mark with quick thinking, excellent strategic planning, and working with others to find the best solutions.