This dissertation contains three essays in labor economics with a focus on economic and institutional differences in regional labor markets. It separately explores the causes and consequences of two major trends in the United States - the declining geographic concentration of immigrant location choices and the increasing prevalence of state-level occupational licensing requirements.

Chapter one shows that the geographic concentration of the foreign-born population in the United States fell sharply between 1980 and 2010 as immigrants were increasingly drawn to areas with historically low migrant inflows. This trend was driven primarily by the changing location choices of new immigrant cohorts, though secondary migration has played a minor role as well. An analysis of the determinants of location choice across four decades suggests that immigrants remain highly responsive to local labor market conditions, but the traditionally strong pull of ethnic enclaves has diminished over time.

Chapter two describes the construction of a novel dataset that compiles over one hundred years of occupational licensing, certification, and registration requirements in all fifty states and the District of Columbia. The data are assembled through a comprehensive analysis of numerous primary and secondary sources and currently identify major state and federal policy changes for 250 unique occupation categories. It is the first occupational licensing database to link each policy to both current statutes or administrative regulations, as well as to historical legislation covering the entire twentieth century. A comprehensive analysis of state session laws, in particular, allows me to observe the exact text of all legislative acts enacting, amending, or replacing statutes that reference specific occupations. Using the content of these laws, I record the enactment and effective dates of regulatory changes and several variables that characterize the type of regulation that was adopted. Relative to existing sources, my data offer a significantly longer time series, the ability to observe superseded legislation, and a more complete coding of legal prohibitions that differentiates between practice and title restrictions.

Chapter three studies the short- and long-run impact of occupational licensing on labor market outcomes in the United States using the data described in chapter two. I implement an event study design that exploits within-occupation variation in the timing of licensing statutes across states to trace out the dynamic response of earnings and employment to policy changes. I find consistent evidence across several independent employer and household surveys that the typical licensing statute adopted during the past half-century increased worker earnings, but had null or weakly positive effects on employment. Twenty-five years after licensing statutes were adopted, cumulative wage growth in treated state-occupation cells exceeded that of untreated controls by 4 to 7%. Over the same time period, my results rule out an average disemployment effect greater than -5%. The data show much larger decreases in employment, however, among occupations that have little potential to cause serious harm. In cases where the consumer protection rationale for licensing is more plausible, I find simultaneous increases in both earnings and employment following the adoption of licensing requirements.