The dramatic development of information and communications technology, the increased speed of scientific and technological progress, and the increased global competition led to the growing importance of knowledge and technology for economy. Modern economy, therefore, increasingly includes features of knowledge economy, an economy based on production, distribution and use of knowledge. Also, more and more the growth of companies depends on innovation, and innovation is based on knowledge. This chapter presents an overview of knowledge economy. It describes the categorisation and a characteristic of knowledge, analyses features of knowledge assets, describes the reasons for the importance of information and communications technology for knowledge economy, and the economic aspects of knowledge assets. Finally, it describes the production, transmission and dissemination of knowledge, as well as the measurement of knowledge required for providing adequate economic indicators for the new economy.