The president then walked Obama from the Oval Office to his motorcade at 3:45 p.m. Obama headed for Reagan National Airport where he was going to hold privae meetings before returning to Chicago.
Obama's top aides made it clear during weekend news shows that the incoming president is considering using executive orders to change the policies of the outgoing president. Those orders could expand federal funding for stem cell research and reverse a recently enacted Bush order allowing drilling for oil and gas in some of the country's pristine reserves.
John Podesta, who heads Obama's transition team, was blunt about the drilling order on "Fox News Sunday." He said the Bush administration wants drilling "in some of the most sensitive, fragile lands in Utah that they're going to try to do right as they -- walking out the door. I think that's a mistake."
There are other public points of the contention between the two men. Obama said in his first news conference Friday since winning the election that he would like the administration to pass a second economic stimulus, something that the Bush administration is resisting.
And Obama's supporters are pressing him to promptly keep his campaign promises. The American Civil Liberties Union took out a full-page ad in some newspapers today quoting Obama's vow to shut down the terrorist prison in Guantanamo Bay. The ad asks Obama to follow through "on day one."
Nevertheless, Obama said Friday, "I'm not going to anticipate problems. I'm going in there with a spirit of bipartisanship."
The presidential changeover is taking place with major steps and small ones. For instance, the Secret Service came up with its code name for the incoming president, Renegade. Michelle Obama will be known to those who talk into their sleeves as Renaissance. The monickers for the Bushes is Tumbler and Tempo.
On a grander scale, Obama opened his transition office in Washington today and he is expected to announce more staff appointments this week, likely press secretary, White House counsel and domestic policy advisers.
High ranking economic and national security advisers and Cabinet secretaries are not expected to be unveiled this week.
Obama is being careful not to undermine Bush while waiting to take office Jan. 20. Obama will take part in a Veterans Day wreath-laying ceremony in Chicago Tuesday, but he has other public events scheduled.
For Obama, today's visit marks a complex transition down Pennsylvania Avenue -- from the legislative branch, governed by the first section of the Constitution, at one end of the street, to the executive branch governed by the second at the other.
"It takes a long time to figure out that the culture of Article 1 is very different than the culture of Article 2," Stephen Hess, a Brookings Institution fellow who served on the staffs of Presidents Eisenhower and Nixon and advised Presidents Ford and Carter, said Friday during a panel.
The White House meeting today was one of many cooperative moves both Bush and Obama have vowed will be a hallmark of the transition.
Obama has suggested he will select Republicans as well as Democrats for key positions. Incoming chief of staff Rep. Rahm Emmanuel, D-Ill., reiterated Sunday on "This Week With George Stephanapoulos" that that's the way Obama will govern.