Introduction - general environmental attitudes and regulatory background; concept of environmental hazard (risk) - definitions; types of recognized hazards - chemical, radioactive, noise, vibration; recognized contexts of environmental hazards - temporary storage, production, products, processes, transport, waste, end-storage, leaks; to whom the duty to disclose attaches - producers, operators, individuals, companies, holding companies, corporate officers, company employees, lenders, corporate successors, transferors, trustees, licensees, importers, exporters, public authorities; to whom disclosure is required - public authority, public at large, sector (how determined), buyers, leasees, licensees, invites; information to be disclosed - mere existence, full assessment; how and when hazard is to be disclosed - via media, notices, direct; who oversees and /or compels disclosure - public agencies, private persons; consequences of non-disclosure, improper or insufficient disclosure, and disclosure - public (licensing, cleanup, penalties), private (avoidance of transaction, liability, recoverable damages, standing to claim damages); bona fides, defences, excuses, limitations, time bars; territorial application, international private law aspects; conclusion.