Here is a question about this article: Traditionally, Shell was a heavily decentralised business worldwide (especially in the downstream) with companies in over 100 countries, each of which operated with a high degree of independence. The upstream tended to be far more centralised with much of the technical and financial direction coming from the central offices in The Hague. Nevertheless, there were very large "exploration and production" companies in a few major oil and gas production centres such as the United Kingdom (Shell Expro, a Joint Venture with Exxon), Nigeria, Brunei, and Oman.
What is the answer to this question: What types of companies existed in a few major oil and gas production centers?
"exploration and production"