In their report Solid Waste Management and Greenhouse Gases: A Life-Cycle Assessment of Emissions and Sinks, the EPA described life-cycle analyses of several materials commonly found in U.S. municipal solid waste and determined sources and magnitudes of greenhouse gas emissions. Based on the study, the EPA also developed an Excel model, WAste Reduction Model (WARM). Managers of municipal solid waste operations can use WARM to determine how changes in their system will affect greenhouse emissions from solid waste management in their municipality. The goal of my project was to first evaluate the study and determine areas that I can improve, then to implement those changes, either by adjusting WARM or by creating my own spreadsheets. After evaluating the EPA report, I developed my version of WARM by modifying the original spreadsheet. Most of the changes I made were replacing some of EPA’s worksheets with my own. These worksheets are hidden in the original version of WARM; the user does not see the worksheets where calculations are made. I also hid the worksheets I created for calculations and left visible only the worksheets that display results, as in the original version of WARM. My version of WARM can be used just as the original is used.