This book presents the economic theories with regards to the entrepreneur of yesterday and those of more recent years, on which issue research has been developing exponentially since the last third of the 20th Century. Much of this book will be devoted to contemporary theories. This presentation of economic theories of the entrepreneur leads us to wonder about the structural development of the free enterprise system in the short and the long term. The proliferation of entrepreneurial initiatives leads in effect to a profound transformation of modes of production and work, for example under the current phenomenon of uberization economy.