Limestone and dolomite quarries were mapped to determine specific slope failure mechanisms for the various geological and structural conditions. Wedge failure and plane failure were determined to be the most influential mechanisms. Algorithms for analyzing these mechanisms were incorporated into the software package PSLOPE. The program is designed to facilitate progressive stability evaluation of quarry high walls as mining continues and permits calculation of safety factors and probabilistic reliability. Safety factor evaluations with the potential for back-analysis and sensitivity studies are included to investigate alternative high wall designs. Reliability analysis using Monte Carlo sampling minimizes uncertainty and allows the use of all available data in a stability evaluation. E~tensive "help" menus are incorporated into the program. The "help" menus include ranges of physical properties such as cohesion and friction angle for specific lithologic units determined from published research. This package includes an optimum design protocol that can be followed to avoid massive failure. The program was developed in conjunction with the quarry industry and is demonstrated through technical problem solving and a detailed case study. A large carbonate quarry in the eastern U.S. was studied in detail to demonstrate the utility of PSLOPE.