WASHINGTON  There is one addiction President Obama will not have to kick: his BlackBerry.

For more than two months, Mr. Obama has been waging a vigorous battle with his handlers to keep his BlackBerry, which like millions of other Americans he has relied upon for years to stay connected with friends and advisers. (And, of course, to get Chicago White Sox scores.)

He won the fight, aides disclosed Thursday, but the privilege of becoming the nation’s first e-mailing president comes with a specific set of rules.

“The president has a BlackBerry through a compromise that allows him to stay in touch with senior staff and a small group of personal friends,” said Robert Gibbs, his spokesman, “in a way that use will be limited and that the security is enhanced to ensure his ability to communicate.”

First, only a select circle of people will have his address, creating a true hierarchy for who makes the cut and who does not.