Abstract
The effectiveness of environmental impact assessment depends largely on fully implementing cost-effective mitigation and other management measures to prevent significant environmental degradation. Follow-up, management systems and monitoring are tools to achieve this. Their role is discussed in relation to a highway in São Paulo State, Brazil. A robust follow-up scheme was the main driver for the successful implementation of mitigation measures. Follow-up costs represented 1.4% of total project costs. Some lessons learned could form recommendations for similar projects: a management system is a powerful tool to implement mitigation and other management measures; checklists and audit protocols can be a practical solution to ‘translate’ the terms and conditions of the environmental license into enforceable, manageable and verifiable rules; external control is essential to guarantee successful implementation of mitigation measures.