Laura Desmond

CEO, Starcom MediaVest Group

In 2006, when Laura Desmond took charge of Starcom MediaVest Group's North American operations, she told Ad Age : "Digital won't be an option, it will be a mindset." It's this kind of foresight that has boosted the network's capabilities and portfolios and pushed her up the ranks. She joined Publicis in 1987 as an associate at Leo Burnett Media. Now, Ms. Desmond is global CEO of the Publicis Groupe media network.

She is the only female CEO running a global media agency network with three agencies -- and controls some of the biggest multibillion-dollar ad budgets in the world.

"I grew up in a world where I was given the confidence to search for and reach my potential," she said. "I see it as part of my job to pay it forward. Helping others be extraordinary is the best legacy we can leave the industry."

Kirsten Flanik

Managing Director, BBDO, New York

Kirsten Flanik can easily be considered among the most important female executives -- and part of the secret sauce -- at one of the biggest agencies in the world, BBDO. Her account-management prowess was integral to its winning back the Snickers business in 2009. Since then, she's grown the agency's revenue on the Mars account 75%.

The Florida native says her two mentors are her mother, a public school teacher, and BBDO chief creative, David Lubars. "From Day 1 he believed in me and pushed me to be my best," said Ms. Flanik. "He instilled confidence in me, showing me the power of small wins and how small wins motivate you to achieve bigger wins."

Wenda Harris Millard

President-Chief Operating Officer, MediaLink

Need an introduction to just about anyone in advertising? Ask Wenda Harris Millard. A tireless networker who is found at almost every major industry event, Ms. Millard is president of the strategic-advisory firm MediaLink and is as likely on any given day to be meeting with a global company like GE or Unilever to talk digital strategy as to be advising an ad-tech firm or an emerging media player like Buzzfeed or Machinima on how to accelerate growth. She's a former chief sales officer at Yahoo and former co-CEO of Martha Stewart Living.

Karen Kaplan

President, Hill Holliday

These days, it's rare that agency presidents began their careers as receptionists. It's even less common that they become president of the agency they started out at. But that 's exactly how Karen Kaplan, president of Interpublic's Hill Holliday, began her advertising career in 1982. Thirty years later, she's still there.

Ms. Kaplan had no formal advertising education; she studied French literature at the University of Massachusetts and had planned on attending law school. That changed once she landed at Hill Holliday. She quickly scaled the ranks through account management, working on consumer, retail, financial-services and technology accounts, and became president of the agency in 2007.

Jacki Kelley

Global Ceo, UM

As a media agency outsider, Jacki Kelley came to Interpublic Group of Cos.' UM as an agent for change in a fast-moving industry. After a long career in media sales, she joined UM in 2009 as North American CEO and in 2011 succeeded Matt Seiler as global CEO. Ms. Kelley has been a proponent of pay-for-performance compensation and brought in some of the firm's biggest clients, such as Chrysler.

"Consumer behavior and technology will continue to force us to reimagine how we serve clients and how we run our companies," she said. "My hope is to always be part of the crowd that is pushing new thinking forward and part of an organization that encourages and celebrates this."

Donna Speciale

President, Turner Entertainment & Animation Ad Sales

Donna Speciale was one of the best-known ad buyers in the industry, helping break down the silos between traditional TV and digital video while at MediaVest, before she switched sides in March to head up Turner Broadcasting's ad-sales team.

Ms. Speciale started in the industry in 1989 as a buyer at Grey Advertising and worked her way up to become the director of national broadcast at the company's media arm, MediaCom, before joining Publicis Groupe 's MediaVest USA in 2004.

At MediaVest, Ms. Speciale's client roster read like a who's who of blue-chip marketers, including Procter & Gamble, Kraft Foods and Coca-Cola. It was here she created the video investment and activation group, pushing clients to consider buying "video" rather than simply linear TV, and cross-trained her sales teams to unite platforms.

In her new role, Ms. Speciale oversees the sales team at Turner's portfolio of channels, as the network beefs up its own digital offerings with the recent investment in Funny or Die, acquisition of Bleacher Report and partnership with DumbDumb.