This work evaluates municipal solid waste (MSW) management options with respect to energy and environmental indicators. Two alternative scenarios have been analyzed: incineration of waste after mechanical biological treatment (MBT) and mass burning. The city of Kaunas, Lithuania, served as an object of the research. The calculations revealed that in the case of incineration of MBT-processed waste, only 2.4-2.8% of municipal heat energy requirements may be satisfied, while mass burning may provide up to 20% of integrated municipal heat energy requirements. The incineration of MBT-processed waste would result in 36% higher exhaust gas volume, 39% higher HCl emissions and 57% higher SO₂ emissions per ton of waste, compared to mass-burned waste. The presented approach may be applied to countries experiencing transitions of MSW management systems.