The Commitment to Development Index has been developed to assess seven policy areas of rich countries that affect the development of poor countries and to rank the rich countries from this perspective. This article aims to analyze the environmental component of this index. The environmental dimension is a legitimate part of the concept behind the index because preserving global environmental resources is essential for the future development prospects of poorer countries. The operationalization of the dimension, however, gives rise to several issues, such as the combination of policy and practice indicators, data availability and credibility, and other specific aspects that affect the information value of individual indicators and the component as a whole. Acknowledging the difficulty of constructing such a component, we suggest several options for its modification.