As b2b marketers shift more marketing dollars online, interactive agencies are ramping up their service offerings, measurement capabilities, talent and global reach to keep up with the demand.

Last year, interactive ad spending reached an estimated $21.1 billion, up 25.0% over 2006, according to the Interactive Advertising Bureau.

“We are really seeing things change in the b2b space,” said Laura Lang, CEO of Digitas USA, winner of this year's interactive agency category. “There is an acceleration of demand as [b2b marketers] embrace the digital channel.”

However, along with the demand comes pressure on agencies to provide new services, as well as prove return on marketing investment.

“Everybody wants to figure out a way to take all the information and make the spend on marketing dollars more accountable,” Lang said. “Clients are asking for better metrics, more timely metrics and the ability to connect it back to business outcomes.”

To help meet this demand, Digitas last year launched Global Marketing Navigator, a Web-based application that helps clients analyze marketing data across multiple channels. It also formed Digitas Global, a new division to grow the agency's international business, and it acquired interactive agencies in China and France.

Another important area in which interactive agencies are expanding is strategic consulting, where they are serving more as a partner with clients to help them identify business objectives and determine how best to meet them.

Tocquigny, runner-up in the interactive agency category, provided more strategic consulting services for clients last year.

“One of the things that we noticed to be significantly different [in 2007] versus past years is the degree to which our clients are embracing, and are hungry for, strategy and insight,” said Yvonne Tocquigny, CEO of Tocquigny, Austin, Texas. “That part of our business has blossomed this past year. We've had a closer partnership with most of our clients because of that than we have experienced in years past.”

Tocquigny provided strategic consulting to new client MessageLabs, for example, helping the Web services provider define customer segments and developing an integrated marketing program to reach them, with a strong focus on testing and measurement.

It also expanded its research capabilities, including custom research for Dell to help it increase its presence in the health care vertical.

Other agencies are growing their interactive services through acquisitions and partnerships. HSR Business to Business, Cincinnati, this year's runner-up in the medium agency category, formed a partnership with interactive agency ClearGauge, Chicago, to strengthen its analytics offering. Under the partnership, HSR and Clear-Gauge are delivering such interactive marketing services as analytics and online creative, as well as develop-ment of Web applications and Web sites.

“The work they've done in Web site analytics in the b2b space aligns perfectly with our 100% focus on b2b work, said HSR CEO Rick Segal.

HSR is also beefing up its search capability with the recent hiring of a new director of search, and the agency is also creating new services in Web 2.0, experiential marketing and mobile marketing.

Interactive agency Atmosphere BBDO is also expanding it services in areas including social media, mobile marketing and analytics.

“There is a lot of appetite [from clients] in exploring all of the new dynamics that are emerging in this space,” said Andreas Combuechen, CEO-chief creative officer at New York-based Atmosphere BBDO.

“From social media to HD Web to high-level rich media content, there are a lot of opportunities,” Combuechen said. “The social media space is getting more and more robust, especially as it relates to b2b. Another important space is mobile. Clients are really beginning to implement activity on the phone.”

For example, the agency developed a mobile application for FedEx tied into its NASCAR sponsorship, in which users could sign up to receive phone calls from race car driver Denny Hamlin.

To handle the growing demand for new services, Atmosphere recently hired a new mobile advertising director, as well as a director of strategy and analytics, a new position, to lead integration of business strategy and data-driven insight into the agency's creative product.

Mary Morrison contributed to this report.