Brussin, 38, already had the launch of three marketing-focused technology companies under his belt when big data analytics began to rise in popularity among technologists. The concept promised a more sophisticated way to use and interpret data, and gave Brussin a new tool to help address the question that has nagged him for nearly two decades: Why is it so hard for marketers to reach customers online?

“The promise everyone was excited about really went undelivered. Marketers told stories that illuminated their frustration,” Brussin says. “A senior executive at a big multi-channel retailer said they could print and ship signs and merchandise for physical stores, set themselves up for a big campaign much faster and less expensive than they could change their website.”

In January 2008, Brussin and David Bookspan formed Monetate in Conshohocken, Penn., just outside Philadelphia’s city limits. The young company — which provides testing, targeting, and personalization for the e-commerce efforts of major retailers — had just one employee but the backing of the venture capital firm First Round and one of its seven partners, Josh Kopelman. By March, Monetate added two more employees, and it stayed that way for most of the rest of the year.

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Today, Monetate packs 220 casually dressed employees into a converted warehouse with high ceilings, exposed ducts and pipes, zero offices, and a great deal of standing desks. In the lounge, there’s a large television for watching Phillies games, among other things. At 5 p.m. every Thursday, the entire staff meets for a roundtable discussion — over pizza and beer, of course — about what was accomplished that week. It’s a tradition that began when Monetate’s staff could be counted on one hand, and one that Brussin isn’t particularly interested in discarding.

“Our team has a great personality as a group,” he says. “We respect ourselves, our colleagues, our customers, our competitors. It shines through with how we interact with each other.”

Whatever it is, it’s working. Well-funded (more than $46 million to date) and expanding quickly, Monetate is attracting tech talent from around the region. David Berton is a software engineer from Roebling, N.J., which lies about halfway between New York City and Philadelphia. He says he chose to work at Monetate because of the company’s culture and assemblage of talent.

“Everyone goes to work and tries to do their best, and that’s here as much as anywhere,” Berton, 41, says. “But what’s unique is that everyone truly excels at what they do. There is a high level of confidence. And it’s not really a buttoned-up place to come to work — the reason is to establish a certain level of comfort.”

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Brussin says the relaxed atmosphere is also an attraction for Monetate’s clients — among them are Patagonia, Best Buy (BBY), Macy’s (M), QVC (LINTA), The Sports Authority, Green Mountain Coffee Roasters (GMCR), and The North Face (ORCL).

Cal Bouchard, director of e-commerce at The North Face, said his company signed on in 2012 to refine how it presented products to customers on its website. Monetate added geotargeting so that when it’s snowing in Boston and a customer there visits thenorthface.com, it will display to them boots and heavy coats (and simultaneously for a customer in warm and sunny San Francisco display light outerwear and hiking boots). It also implemented A/B testing capability for components on the page (such the color of the “add to cart” button).

“The better customer experience is really an interactive one,” Bouchard says. “How online shopping and e-commerce has evolved, it’s very iterative. The [work] that Monetate does allows us to keep up with our changing customer. We give them a better customer experience when we’re able to understand what they’re browsing. We then serve them up another product they might be interested in. That’s powerful.”

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The market in which Monetate operates is quite crowded. In addition to a long list of startups (from Act-On to Vocus), Monetate is competing with some of technology’s largest operators: Salesforce (though ExactTarget and Pardot) (CRM), Adobe (Campaign) (ADBE), Oracle (Eloqua) (ORCL), even IBM (IBM). All mirror the industry’s move to an integrated, cloud-based, automated software-as-a-service system; all are competing for a piece of a digital ad spend estimated to reach $137 billion worldwide this year — an increase of almost 15% from 2013, according to eMarketer.

Brussin doesn’t seem overly concerned about the fight ahead. “When I think about where market is today … it’s still in broadcast mode,” he said. “That difference is stark, kind of shocking, and disturbing to the customer. Hearing from brands [rather than having a conversation], it kind of feels impersonal and robotic. Marketers have realized they have to fundamentally change their approach to marketing. The challenge is that marketers are still stuck with their own tools. What they really have is a broadcast tool set. They know their brands have to change to survive and thrive.”