Rapidly rising atmospheric CO2 concentration and its potential impact on future climatic conditions is an issue of global economic and political significance. Natural biomass respiration is a major carbon source. Understanding soil flux and its relationship with other sources and sinks within the carbon cycle are currently subject to increasing scientific scrutiny. The new ADC BioScientific ACE system (Automated soil CO2 Exchange system) is designed for the long-term, unattended monitoring of soil flux. The automated design allows the soil area to be exposed to ambient conditions between analysis cycles. The soil chamber then automatically closes prior to soil flux measurements being made.