This document summarizes a presentation about economic research on diversity through international migration. It discusses several topics covered in the research, including measuring diversity through indexes, the impact of migration on wages and employment, productivity and innovation, and trade. It notes that research finds diversity has a small but positive impact on wages and employment, and that among firms that hire skilled immigrants, greater diversity of foreign workers enhances product innovation. Meta-analyses show an increase in the number of immigrants increases trade volumes by around 1-2%. The presentation concludes by discussing the relevance of this research for policies in New Zealand.