Co-President and Co-Chief Executive Officer Jonathan G. Sloane of Medford-based Century Bancorp, parent company of Century Bank and Trust Co., will take a temporary leave of absence.

Sloane said he needs to address personal issues which are not related to the company or Century Bank.

Barry R. Sloane, currently co-president and co-chief executive officer, will assume all duties associated with these roles during the interim period. Marshall M. Sloane will continue in his role as chairman.

Given the collaborative nature of the current leadership structure, with both Jonathan and Barry Sloane sharing equal responsibility for all aspects of operations, decision making and strategic planning, the company said it anticipates a seamless transition.

"We are fortunate to have operated as a true team with joint decision making responsibilities, and this change will have no impact on bank operations or performance," said Barry Sloane. "I and the team at Century Bank will miss Jonathan’s leadership during his leave, but we recognize and respect his decision to step away from day-to-day executive duties for a period."

Jonathan Sloane has been employed by the company for nearly 30 years, serving in his current position since 2005.

In its year-end earnings, Century Bancorp announced net income of $9 million for 2008, an increase of 15 percent when compared to net income of $7.9 million in 2007.