For a president considered by some to be a lame duck, George W. Bush had a sprightly stride last week.

In a rush before leaving for an August vacation, Congress approved a series of economically significant measures that will open free trade with Central America, encourage more domestic production of energy, and pour billions of dollars into the construction of highways and bridges.

The burst of accomplishment is likely to bolster the president's sagging ratings in public opinion surveys. Pollsters say there's nothing that benefits a chief executive more than getting things done.

But if last week is a harbinger, Bush will have to work overtime -- and be willing to compromise on many fronts -- to win the other big legislative fights that are still to come.

Before the House of Representatives gave final -- and narrow -- approval to the Central American Free Trade Agreement, the president had to travel personally to the halls of Congress to twist arms and cut deals. His trades ranged from promised fundraising appearances by Vice President Dick Cheney to promises not to cut pet agricultural programs. Many of his smaller concessions were quietly tucked into other legislation.

The biggest bargaining chip was the Republican leaders' embrace of a bill, approved by the House last week, that would give U.S. firms expanded means to seek duties on imports from China and other "non-market" economies.

Similar wheeling and dealing preceded passage of energy legislation that the White House had advocated without much progress for nearly five years. The president was forced to lay aside his demands for budgetary restraint to get what he wanted. For instance, his administration had originally sought a 10-year, $6.7 billion tax-cut package as part of the energy measure, but the final bill was more than double that size -- $14.5 billion over the period.

Bush also had to accept a highway bill that was more costly than he had wanted. After haggling for nearly two years, the president accepted a $286 billion measure that would raise benefits for heavily traveled states and improve many mass transit systems. Previously, the White House had warned that Bush would veto any bill that topped $284 billion. Well, so much for unwavering principle in the give-and-take of Capitol Hill.

While important, none of these measures is at the heart of the president's economic agenda. Despite his constant prodding, Bush's top priority -- overhauling Social Security -- has so far gone nowhere in Congress. And while his unexpected surge of success last week will surely boost his chances with that difficult bill, the wrangling has barely begun.

Judging by the manner in which Bush won last week, victory on Social Security will require an extraordinary number of compromises down the road. What Bush wants now probably won't survive at the end. Standing tall with Congress requires a lot of flexibility.