The objective of this study is to develop an econometric model for the diffusion of innovations at the individual country level, but which also allows the parameters of the process to differ systematically across countries. The conceptualization rests on behavioral and spatial theories of diffusion and extends the domain to international markets. The cross-national model of innovation diffusion which is developed highlights substantive differences and similarities among international markets. It also provides estimates for the diffusion parameters, even for countries where sales data are not available, thereby yielding some insights into the nature of the expected diffusion pattern in these countries prior to market entry.