(FORTUNE Magazine) – In the boardroom at Royal Dutch/Shell, chairmen come and go. And hardly anyone, including people who make it their business to track such things, ever notices. ''More than most big companies, Royal Dutch/Shell is very much run by committee,'' observes a respected British oil analyst. ''Whoever is at the top, they just carry on being good at what they do.'' The latest all-but-anonymous achiever to chair the world's second-biggest oil company is a Dutchman, L. C. (Lo) van Wachem, 56. Born in Indonesia, he joined Royal Dutch/Shell after earning a degree in mechanical engineering at the Technologica University in Delft, the Netherlands. After two decades roving from Venezuela to Nigeria to Brunei, he returned to The Hague headquarters to run worldwide exploration and production. Two years ago he became chairman of the committee of managing directors. So far on van Wachem's watch, the company has had a typically unsurprising but impressive performance. It coped with last year's collapse in oil prices as well as or better than any of the other majors. ''I'm not saying we enjoyed it,'' says van Wachem, ''but there was no panic.'' The company's refining and marketing operation remains Europe's biggest and most profitable. Its Houston- based subsidiary, Shell Oil, continues to be the best finder of reserves in the U.S. With more than $9 billion in cash on the balance sheet, van Wachem's strategic task is to decide where to put it.