The Powder River Basin coals contain a considerably larger volume of gas in place than established by previous studies. The Powder River Coalbed Methane Basin Study identifies 61 Tcf of natural gas in-place. This in-place resource value is significantly larger than previously reported and confirms that the Powder River Basin (PRB) coalbed methane (CBM) play has the potential for providing significant additions to future domestic natural gas supplies1. Major reasons for the increased PRB coalbed methane resource in-place of 61 Tcf in this Basin Study are the following: ? The study included extensive information on the deeper Fort Union coals prevalent in the basin, it compiled new data on the Wastach coals on the western edge of the basin, and it included the coals in the Montana portion of the PRB. ? The study identified the presence of free gas in certain coal formations and established higher gas content values for PRB coals, both increasing the gas in- place over previous estimates.