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An evaluation of the original version of the advanced physics moist convection parameterization revealed excessive heating and precipitation being produced by the scheme within the global spectral model. This report describes a series of corrections and modifications made to the parameterization software to improve its performance. Forecast experiments were conducted to determine the effectiveness of each modification. Turning off the entrainment formulation, using a newly developed scheme for computing the lifting condensation level and moist adiabat, employing a center-difference scheme for computing moisture convergence, and allowing evaporation of falling precipitation in the cloudy portion of the grid box yielded the most realistic convective heating and precipitation. This version of the convective scheme was used in a series of 10- day global spectral model forecasts. Global and zonal average distributions of precipitation agreed well with climatological estimates for the same months. Although the modified version of the scheme resulted in substantially reduced convective precipitation, it still produced more than was observed in areas of high climatological rainfall. In the tropics, the modified convective scheme produces too much precipitation in areas characterized by heavy precipitation, and not enough precipitation in the more arid regions. In the extratropics, wintertime convection downstream from continents (typically involved in cyclogenesis) was simulated by the model. Summertime convection over the United States was characterized by too little precipitation in the typically convectively active areas, and too much in the more convectively stable regions of the country.