Amidst increasing pressure for organisations to be environmentally responsible, IT organisations increasingly need to develop their Green IT capability to minimise the adverse impacts of information technology on the environment. This research adopts the theory of absorptive capacity – a dynamic capability that represents the ability of the IT organisation to recognise the value of identifying new and external information, assimilate, transform and exploit this – to identify the processes of, and the factors that influence, an IT organisation’s Green IT capability. Insights from case studies of six organisations implementing and delivering Green IT initiatives are used to develop a set of propositions and a model for Green IT Absorptive Capacity. Findings indicate that the absorptive capacity of IT organisations is reliant on the acquisition of comprehensive external knowledge and prior experience. Government policy, internal social integration mechanisms within the IT organisation and parent organisation and the industry in which an IT organisation operates also influence absorptive capacity and ultimately Green IT capability.