The RGM Group figures out how to enable premium brand advertisers to target rich people via online ads, and it’s has gotten richer itself. The Venice, Calif.-based company has raised $21 million in private equity and hired a new chief executive.

Kurt Johnson, a veteran CEO who previously held the top jobs at FastClick and ValueClick, replaces founder Kamran Razavi as the new CEO of RGM Group. Razavi (pictured right) will remain on board full-time as chief strategy officer.

The funding is the first ever for the company and it comes from Riordan Lewis & Haden Equity Partners . It was aided in the funding by New Century Capital Partners.

“I am very ready for this transition,” said Razavi, in an interview with VentureBeat. “I am an entrepreneur. I like to create. As you scale a company to become bigger, it gets harder to do both. We found someone with the right skills to scale us up.”

RGM is profitable, but it needs the money to aggressively accelerate its national sales, creative, product and technology development efforts. It will try to double its headcount by mid-2013 and focus much of its growth in the New York metro market, where it recently opened a new office. RGM uses its different divisions to reach more than 155 million online consumers, many of them who are considered luxury or premium customers who are valuable to advertisers.

At the age of 25, Razavi founded the company in 2004 and it grew to become a large digital media company — one that most people don’t know. It serves hundreds of premium brands and ad agencies, including Jaguar, American Express, and Sony. The company has 24 employees and it will now try to double that.

“As we looked at opportunities within the rapidly growing digital media industry, RGM clearly stood out as a company well-positioned to deliver differentiated, value-added solutions for premium brand advertisers in a dynamic marketplace,” said J. Christopher Lewis, the managing director of RLH. “We are pleased to have the opportunity to work closely with the RGM team to enhance and broaden the company’s unique platform and to build upon RGM’s solid reputation for delivering the highest quality integrated brand advertising solutions.”

RGM’s three divisions include the RGM Alliance, a premium ad network of 300 publications [disclosure: including VentureBeat], that are vertically focused an organized into 14 content channels. The alliance includes publications such as Frommer’s, Men’s Fitness, and SmartMoney as well as growing niche sites such as Digital Trends, ChaCha, and Urbanspoon. The alliance reaches 144 million U.S. consumers through 8 billion page views per month. Market analyst ComScore Media Metrix says RGM is the No. 1 Fashion channel, No. 2 Travel channel, No. 8 Business channel, and No. 16 Health channel online. RGM still screens its web site publishers so that it only reaches users that premium advertisers want to target.

Another division is RGM Exclusive, which provides exclusive media representation for premium publishers and creates unique and custom ad integrations for advertisers. It creates custom online and mobile brand experiences for select clients. A new publisher includes and other publishers include OpenTable and JustLuxe. The third division is RGM Creative, the creative ad arm of the group.

“Joining the RGM Group as CEO is a rare opportunity to help lead a company that has established the industry’s leading platform for premium national and global brands that directly engages with consumers in the right context of quality digital media,” said Johnson. “With a total reach of more than 155 million U.S. consumers, and deep content integrations with marquee Web sites and publishers, RGM is poised for significant growth as we deliver an expanding array of products to the market at much greater scale.”

New additions to the board include Rob Rodin, former CEO of Marshall Industries, as well as Chris Lewis and Ryan Smile of RLH.

Rivals include companies such as Glam Media, Travel Ad Network, and Conde Naste Digital.