Livestock production is an important source of the highly effective greenhouse gases nitrous oxide and methane. But, accurate quantification of emissions of the two gases from grazed pastures is complicated by extreme spatial heterogeneity. Soils receiving urine and feces inputs are expected to emit the gases at rates that can be orders of magnitude greater than soil receiving no livestock wastes. The current study is being conducted in central Pennsylvania on a pasture which is rotationally-grazed by beef cow/calf pairs. Nitrous oxide and methane emissions are measured separately from points where feces and urine deposition were observed and points that received no waste inputs. Gas emissions are measured with small, vented chambers each 3 to 7 days after grazing until flux rates return to pre-grazing levels. Data obtained following the first two grazes in 2005 showed that nitrous oxide emissions were 6 to 20 times greater from soils which received urine or dung compared to points which received no waste. Methane was emitted only from dung piles. The change in soil ammonium-N concentration at 105 points across the pasture following grazing indicated that approximately 2.0% of the soil surface received urine inputs. Dung piles were counted and their area estimated to indicate percentage of the pasture's surface area covered (<0.5%). Scaling the emissions in proportion with the fraction of the pasture's surface area impacted by waste indicated average nitrous oxide and methane emissions of approximately 9 and 3 g/ha/day, respectively, during June and July. While the small area receiving urine and feces moderates the impact of the high emission rates from these sources, estimates of total emissions of nitrous oxide and methane from grazing lands can not be accurately assessed without appropriate consideration for the emissions resulting from livestock waste inputs.