This thesis contributes to two fields of macroeconomics. The first two chapters contribute to the literature that investigates the role of household heterogeneity, in terms of marginal propensity to consume and labor income, for the ‘optimal’ design of fiscal policies. The first chapter explores how the introduction of household heterogeneity alters the prescriptions derived from the standard optimal fiscal policy framework that only accounts for a representative agent. When heterogeneity is accounted for the government uses taxation and transfers as a redistributing device that only partially corrects for fluctuations in income inequality. The second chapter builds on the results of the first. It develops a quantitative model that is estim...