This is the third of three volumes containing edited versions of papers and commentaries presented at invited symposium sessions of the Tenth World Congress of the Econometric Society, held in Shanghai in August 2010. The papers summarize and interpret key developments in economics and econometrics, and they discuss future directions for a wide variety of topics, covering both theory and application. Written by the leading specialists in their fields, these volumes provide a unique, accessible survey of progress on the discipline. The third volume primarily addresses econometrics, with specific focuses on the econometrics of industrial organization, macroeconometrics, econometric theory, empirical microeconomics, time series and panels, and the Mirrlees Review on tax reform in the twenty-first century.