Sumário:1. Introduction -- 2. The legal status of NGO consultative arrangements -- 3. The legal status of NGOs in general: 3.1 Role in the practive of treaties and conventions; 3.1.1 Advisory level; 3.1.2 Decision-making level; 3.1.3 Executive level; 3.2 State practice in NGO participation in conferences -- 4. Conclusion.