Thesis: This thesis analyzes the accumulation, distribution and taxation of wealth, usingthe Spanish context as a laboratory. The first two chapters have a particular focuson housing. In the first chapter, we reconstruct Spain's national wealth from 1900to 2017. By combining new sources with existing accounts, we estimate the wealth of both private and government sectors and use a new asset-specific decomposition of the long-run accumulation of wealth. We find that during the 20th century, the national wealth-to-income ratio remained within a relatively narrow range–between 400 and 600%–until the housing boom of the early 2000s led to an unprecedented rise to 800% in 2007. Our results highlight the importance of land, housing capital gains and international capital flows as key elements of wealth accumulation.In the second chapter, I study the implications of housing booms and busts forwealth inequality, examining two episodes over the last four decades in Spain. Icombine fiscal data with household surveys and national accounts to reconstruct the entire wealth distribution and develop a new asset-specific decomposition of wealth accumulation to disentangle the main forces behind wealth inequality dynamics (e.g., capital gains, saving rates). I find that the top 10% wealth share drops during housing booms, but the decreasing pattern reverts during busts. Differences in capital gains across wealth groups appear to be the main drivers of the decline in wealth concentration during booms. In contrast, persistent differences in saving rates across wealth groups and portfolio reshuffling towards financial assets among top wealth holders are the main explanatory forces behind the reverting evolution during housing busts. I show that the heterogeneity in saving responses is consistent with the existence of large differences in portfolio adjustment frictions across wealth groups and that tax incentives can exacerbate this differential saving behavior. These results provide novel empirical evidence to enrich macroeconomic theories of wealth inequality over the business cycle.In the third chapter, we study the effect of annual wealth taxes on migration. Weanalyze the unique decentralization of the Spanish wealth tax system following the reintroduction of the tax in 2011. Madrid is the only region that did not reintroducethe wealth tax. Using linked administrative wealth and income tax records, weexploit the quasi-experimental variation in tax rates generated by the reform tounderstand the mobility responses of high wealth individuals and the resulting effect on wealth tax revenue and wealth inequality. Aggregating the individual data to the region-year-wealth tax filer level, we find that five years after the reform, the stock of wealthy individuals and the stock of wealth residing in the region of Madrid increased, respectively, by 11% and 12% relative to other regions prior to the reform. Using an individual choice model, we show that conditional on moving, Madrid's zero tax rate increased the probability of changing one's fiscal residence to Madrid by 24 percentage points. We show that Madrid's status as a tax haven exacerbates regional wealth inequalities and erodes the effectiveness of raising tax revenue and curving wealth concentration.