This paper examines the emergence of the knowledge economy by studying the increasing importance of high-knowledge occupations from 1971 to 2001. Contrary to the impression that emphasizes the recent rapid development of the high-tech information and communications technology (ICT) sector, a more extensive examination of the presence of knowledge workers shows that the emergence of the knowledge economy has been more widespread and continuous than might otherwise be thought. This paper reports that the importance of knowledge occupations has continuously increased over the last three decades. It also examines differences in the changes that have occurred for different knowledge professions (managers, professionals and technical occupations) and for different industries. It finds that the increase in the proportion of the knowledge-based labour force was widespread for professionals, managers and technical occupations, as well as most industries. While there are differences in the rates of growth in some areas, the most important conclusion to emerge from the study is that the growth of skills, as proxied by the importance of knowledge occupations, was widespread and not restricted to narrow areas of interest, such as popularly defined high-tech sectors.