Purpose As an enabler of environmental sustainability, Green information technology has become an emerging topic of interest in both academic and business communities. Despite its importance, confusions exist in the content and scope of Green IT practice. The purpose of this paper is to provide an overview of the current state of Green IT practice. Design/methodology/approach First 14 widely accepted Green IT practice topics were identified from prior research and a taxonomy was developed to categorize them. Using the content analysis (...) method, these topics were examined in the sustainability reports of 30 IT companies in 2014 Fortune 500. A quantity–quality portfolio framework was developed and applied to measure and assess the Green IT practices of the selected samples. Findings Currently, the Green IT practice is still in its infancy. Both research and practice attention are now focusing on IT’s direct impacts and enabling impacts, while overlooking the systemic impacts, on natural environment. The possible reasons for the current state and the recommendations for future research and practice are provided. Originality/value Theoretically, this paper identified 14 widely accepted Green IT practice topics and developed a taxonomy for categorizing them. The taxonomy and topics provide a theoretical basis for future examination on Green IT practice-related issues. Practically, the findings of this paper provide guidelines for Green IT practice and directions for both Green IT developers and adopters in their decision-making. (shrink)