SUMMARY: The starting point of this article is the paradigm shift in cultural policy from the arts to the broader view of the creative industries that has taken place in many countries, in the European Union and in UN agencies. The emphasis on creative industries as a source of economic growth has highlighted the role of creativity and of copyright as an incentive for it. Little is known, however, about the economics of creativity or what economic incentives it responds to and this is a gap in our understanding of cultural supply that requires detailed research. The application of 'crowding' theory to the motivation for creativity forms a basis for that research, as does work in cultural economics on artists' labour markets. Likewise, economists have almost no empirical evidence about copyright as an incentive to creativity generated by individual creators. Research is, however, held back by data problems concerning the measurement of creative industry output and employment and especially of the supply of core creative content, making claims of the impact of copyright difficult to assess. The impetus for the article is to express these concerns and to emphasis the need for empirical research in this area.