Recent research helped in clarifying the nature of short-run price and quantity adjustments in Keynesian macroeconomic models and the possible causes of a persistent excess labour supply. It is argued, however, that theories involving imperfect competition and real wage "rigidities" generate "Classical" unemployment, where multipliers act through supply-side effects, while nominal inertia seems to be at the root of truly "Keynesian" multipliers. The appraisal also contains a nontechnical presentation of recent models of endogenous expectations-driven business fluctuations (cycles, "sunspots"). Monetary policy can then have persistent real effects under complete information ("money as a sunspot").