Please note that the content of this book primarily consists of articles available from Wikipedia or other free sources online. Xavier Musca (born February 23, 1960 in Bastia, Corsica) is a French economist, writer, and public administrator. As of February 26, 2009, he is the Deputy Secretary-General of the French President Nicolas Sarkozy's Office. An economist is a professional in the social science discipline of economics. The individual may also study, develop, and apply theories and concepts from economics and write about economic policy.