MARK SANFORD HAS sometimes displayed an almost blind faith in the merits of privatization. During his campaign for governor, he went so far as to propose that state agencies be required to convert a targeted percentage of their operations to the private sector.

That proposal, along with comments he has made since taking office, made it look uncomfortably like Mr. Sanford was willing to ignore any facts that might get in the way of his philosophical adherence to privatization. After all, it often costs less for government to provide a service than a private company, which expects to make a profit. And there are many government functions that would be entirely inappropriate to turn over to the private sector.

But when he rolled out the first preview of his upcoming state budget proposal Tuesday — a plan to sell off a third of the state’s automobile fleet and move to rentals and long-term leases with private companies — Mr. Sanford enunciated some sensible principles for making decisions about turning tasks over to the private sector. Indeed, the principles offer valuable guidance for distributing the workload within government and deciding which tasks should be the responsibility of government at all.

“Government,” Mr. Sanford said, “ought to focus on things that only government can do.” He cited as examples the military and the court system.

The governor went on to say that “it doesn’t make sense for government to do things that can be handled in the private sector.” We would add, perhaps more emphatically than he always does, that this makes sense only so long as the private sector can perform the task for less money than the government — an idea that seems to have eluded our Congress recently. But one of his reasons for making that argument — that having government do things that could just as well be done by businesses “takes our attention away from core government functions” — is critically important.

As Mr. Sanford correctly noted: “We do too many things in this state. We duplicate effort, and that as a whole makes for expensive government.”

It’s too soon to judge the merit of his state fleet proposal. It sounds reasonable, but we’d like to see someone in addition to the governor’s office examine the math, and we’d like to see if anyone can explain why the lower cost Mr. Sanford believes he can achieve in the private sector is still higher than what North Carolina pays to operate its own state fleet. But we’re delighted that Mr. Sanford has put forth a proposal that should force us to address such questions.

We’re even more delighted to hear Mr. Sanford’s promise that this and other proposals we’ll soon see in his budget came as a result of asking more general questions: “Are there things that we don’t have to do as a state? Are there things that could be handled by one agency instead of three?”

Those are questions that have not been asked often enough in the past. Now that Mr. Sanford has asked them and is making some proposals based on his own answers, it will be incumbent on our Legislature to ask the more specific questions about each proposal. It would be a mistake either to rubber-stamp his proposals or to ignore them altogether.