This thesis contains five empirical studies of the determinants and effects of innovation and technology adoption. Chapter 2 investigates the skill-bias of Information and Communication Technologies (lCT) using a unique dataset of manufacturing firms in Brazil and India. Two main empirical approaches are taken. First, I estimate the relationship between adoption of ICT and changes in employment shares of skilled workers at the firm level. Second, I exploit exogenous variation in the relative supply of skills across states within each country to show that ICT adoption is higher in states with a larger relative supply of skilled workers. The next two chapters examine the geographical location of R&D and its impact on the diffusion of knowledge. Chapter 3 uses matched firm-level accounting and patent data to examine whether UK firms with a high proportion of US based inventors are better able to access US R&D spillovers. Chapter 4 uses novel data on levels and changes in university research quality in the UK to examine the extent to which domestic and foreign-owned R&D labs are co-located with relevant university research. Chapter 5 examines the impact of product market reforms on innovation and productivity growth in EU countries during the 1990s. The chapter exploits exogenous variation in the impact of the 1992 Single Market Programme to show that product market reforms were associated with higher R&D spending and faster productivity growth. Finally, Chapter 6 examines the productivity impact of ICT in Brazil and India. I find extremely high estimated returns to ICT capitaL even after controlling for firm fixed effects and investments in organisational change. Within India I find that ICT capital intensity is lower in states with worse infrastructure quality and more pro-worker labour regulation, while the returns to ICT are lower in states with worse infrastructure quality.