Green Activity Based Management (ABM) is a bottom-up approach for environmentally sustainable business process management. This approach extends Activity Based Costing (ABC) and Critical Path Method (CPM) principles for the purpose of capturing, measuring, modelling and reporting Greenhouse Gas (GHG) emissions. The Green ABM not only looks at GHG emissions but also considers cost and time as well. Thus, this provides a holistic picture of these inter-dependent dimensions to the organizational manager for decision making. Furthermore, this research shows that Green ABM can be used to minimise the costs associated with the timing of activities while keeping other business objectives in consideration.