This chapter examines the diffusion of ICT across OECD countries. It uses official statistics, which may differ substantially from previously published private estimates of ICT diffusion. It shows that ICT networks continue to diffuse throughout the OECD area, even during a period of slower growth. However, large differences in the uptake of technologies persist across the OECD, both between and within OECD countries. Cost differentials and structural differences are among the factors explaining these differences, as is the state of the business environment in different OECD countries...