Reyes, 53, is credited with helping Google woo Wall Street, despite some controversial statements about the company and its industry. Reyes said he plans to stay on board to assist Google in the search for his successor and to assure an orderly transition. Google executives said they expect to have a new CFO in place by the end of the year

“As Google’s CFO, George successfully navigated our innovative IPO, the regulatory demands of Sarbanes-Oxley, and the management challenges of scaling a global finance organization,” Google Chairman and CEO Eric Schmidt said in a statement. “Though we fully appreciate his decision to step back from active management, we’ll miss his thoughtfulness, good humor, and wisdom.

CFO Search Begins

With those words, Google’s search for a new CFO officially begins. Filling those shoes might be difficult, though. During Reyes’ tenure, Google saw revenue swell from $439.5 million in 2002 to $10.6 billion last year. The staff grew from 682 at the end of 2002 to 13,786 as of June. Google is a much different company than it was when Reyes signed on for the job.

“You need an executive with a different set of skills to take a company that has grown like Google to the next level,” explained Marc Pado, a stock analyst at Cantor Fitzgerald. “Reyes took a small company and helped build it up. Google may need another executive to expand its horizons.”

The resignation of Reyes, the CFO who took Google through its 2004 IPO, has not negatively impacted Google stock. Pado said he anticipated a possible downtick on the announcement, but noted that the market’s reaction could mean that investors are looking at Reyes’ resignation as an opportunity to bring in some fresh blood for Google’s next growth phase.