This is Peter Orszag's last day on the job. His tenure as director of the Office of Management and Budget has been short: The administration is not yet two years old and Orszag will be the first cabinet official to leave it. But, as Ben Smith notes today, Orszag's impact has been substantial and it will likely be long-lasting.

Orszag brought to the White House two strong beliefs: That rising entitlement spending was going to create unsustainable budget deficits and that the only way to reduce that spending was by controlling health care costs. And, from start to finish, he was true to both of those.

Within the White House and in negotiations with Congress, he was a frequent voice for spending restraint and a champion of cost control in health care reform. It's entirely possible that, without Orszag, the final reform bill might not have included (a) an independent commission to calibrate Medicare payments and (b) a tax on benefits that should discourage expensive health insurance plans. Thanks to legislative compromises, the commission is relatively weak and the tax doesn't phase in for a few years. But both measures should have some impact and, more important, they create levers that future lawmakers can use to reduce health care spending more dramatically.

Not everybody in the administration or on Capitol Hill is sad to see Orszag go--for a combination of reasons that, as Smith notes, span the personal and the philosophical. To the extent I have been familiar with internal debates, I've sometimes learned that Orszag was to my right--putting perhaps too much emphasis on spending reduction or, during the health care fight, giving insufficient priority to guaranteeing that all people have not just insurance but adequate insurance. Still, health care reform also needed strong cost control, for political and policy reasons. Orszag deserves credit for that.

Indeed, my primary complaint about Orszag is actually about the people around him--or, more accurately, the people who aren't around him. The Obama Administartion is an experienced, talented bunch. But while they all know a great deal about policy, few of them seem to feel that strongly about it except in the very broadest sense. And those that do--mostly, the administration's economists--share Orszag's center-left perspective with a tilt towards the center. As Paul Krugman asks today, "Did all the senior members of the economics team have to be protégés of Robert Rubin, the apostle of financial deregulation?"

No, they didn't. Orszag did his job and he did it well. I suspect the administration could have used a few more people with the same skill set--and a different philosophical perspective.