The monetary and fiscal policy interactions have gained a new research interest after the 2008 crisis due to the global increase of fiscal debt. This paper constructs a macroeconomic model of joint fiscal and monetary policy for an emerging open economy taking into account its structural uniqueness. In particular, the two instruments of monetary policy, interest rate and foreign exchange intervention; the two instruments of fiscal policy, government consumption and government investment; and a sudden stops shock through the collateral constraint of foreign borrowings are modeled here in a single DSGE framework. The parameters are calibrated for the case of Hungary using data over 1995Q1-2011Q3. The impulse response functions show that government consumption is unproductive and increases fiscal debt as opposed to government investment, foreign exchange intervention positively affects net exports but does not stimulate an economy per se causing inflation, and a negative shock to the upper bound of leverage ratio in the collateral constraint of foreign borrowings generates a sudden stops crisis for the emerging world. Monetary and fiscal policy intimately interact in the short and medium run such that there is an immediate response of monetary instruments to fiscal shocks, while fiscal instruments adjust to monetary shocks in the medium run.