This evaluation assesses the Bank Group's support for environmental sustainability—in both the public and private sectors—over the past 15 years. It identifies several crucial constraints that need to be addressed, perhaps most importantly insufficient government commitment to environmental goals and weak institutional capacity to deal with them. But constraints within the Bank Group, including insufficient attention to longer-term sustainable development, must be reduced as well. The Bank Group needs improved systems in place—across the World Bank, IFC, and MIGA—to monitor environmental outcomes and to assess impacts. Better coordination among the three parts of the Bank Group is also among the key challenges.