The present paper explored the relationship between environmental sustainability and the use of IT. Based on interviews with seven “Green IT” experts and evangelists, we constructed a questionnaire for CIOs on this important issue. After collecting interview data from CIOs in ten organizations, we found that organizations are at different levels of maturity regarding environmental sustainability and IT use. The maturity levels ranged from an awareness of the sustainability issue to implementation of specific practices to promote environmental sustainability through IT use.