The new macroeconomics is about distributions and flows, rather than points and intersections. Market frictions imply that the search for trading partners is time consuming and costly. Consequently, market participants flow between economic states, and trades occur at dispersed prices. This generates motives for continued search for better market opportunities, and for bargaining between potential trading partners. This volume takes the empirical analysis of markets with frictions to a new level by using unique merged registers from Denmark on firm accounting data, individual employee data, and international trade data to estimate empirically the relevant flow rates, dispersions, and relations among key variables of interest, including productivity, firm size, wages, exports, growth, and unemployment. The results serve to inform researchers and policy makers about the functioning of markets, justify the interpretation of dispersion and flows as equilibrium outcomes, and provide an understanding of cycles, adjustment, and potentials for public policy.