Every building should be thought of as an organism that evolves over time after it is ‘finished’; the architects and engineers who design it are responsible for setting up the most carbon-efficient process for the building’s whole life. The starting point is a client decision to include embodied and whole life carbon (WLC) accounting within project objectives as a key performance indicator – a choice that clients are increasingly making. A carbon consultant must be selected to provide the required level of advice. The carbon consultant can assist with concept development by providing comparative WLC assessments of various building fabric options being considered, as well as the carbon cost/benefit relationship with operational environmental strategies. Low carbon choices are integrated into the detailed drawings, specifications and tender documentation, with support from local assessments. The key issue is monitoring the actual carbon impacts of the construction process against the carbon budget, and what has been agreed on completion of the tender process.