Climate change is the issue of the century and, according to Agenda 21, local actions are essential to impact global mitigation of greenhouse gases (GHG) emissions ("think globally, act locally"). However, in order to plan and implement effective, sustainable actions, local authorities need detailed information on their GHG emissions and their sources. This paper presents the work that led to the development of a GIS-based tool for local GHG accounting, which provides data for local decision-makers in an innovative manner different from traditional GHG inventories. The original aspects of the study are the geo-referencing of all results and the possibility of calculating all emissions (carbon sources) and removals (carbon sinks) with input data of different accuracy. (C) 2013 Elsevier Ltd. All rights reserved.