The thesis comprises two essays that investigate the theoretical properties and empirical performance of dynamic equilibrium models designed to account for the phenomena of aggregate economic growth and unemployment.;The first essay, entitled Business Cycles and Labor Market Search, is primarily interested in providing a quantitative assessment of a particular brand of search/unemployment theory in the context of a dynamic, stochastic, general equilibrium business cycle model. In order to ascertain the likely quantitative importance of the propagation mechanism induced by the search environment, an artificial economy is parameterized, calibrated, and simulated. The statistical properties of the simulated business fluctuations are then compa...