"The Vietnamese know that investors want to make prudent investments," he said.

Are the goals of drug science too chancy for prudent investment?

I agreed with him at the time about the extra expense, which he said was a prudent investment for the future.

But his larger point - that economic growth calls for prudent public investment - is exactly right.

"It was considered a prudent investment at the time," he said.

Priced at about 10 cents they seem a prudent investment, in good luck if nothing more.

I know which I think is the more prudent investment!

Spending to increase a software product's market share, or slow its erosion, is a prudent investment.

"Is it a prudent investment of public money to solve something that might happen two times in 250 years?"

"We're trying to turn it into a prudent investment," he said.