This Practice Note discusses environmental issues in bankruptcy, including the treatment of claims and regulatory obligations, dischargeability of environmental claims and exceptions to discharge, bankruptcy court jurisdiction over environmental claims, and strategies for addressing contingent environmental claims including claim estimation and disallowance of contingent contribution claims under section 502(e)(1)(B). This Note also discusses exceptions to the automatic stay for governmental agencies, including the ability to enforce regulatory compliance and impose statutory liens, and standing of governmental agencies and advocacy groups to be heard in bankruptcy cases. It also addresses strategies for addressing regulated executory contracts such as wholesale power contracts and midstream oil and gas transportation service agreements, disposing of contaminated property in bankruptcy, special environmental considerations in mining industry bankruptcies, and lender liability issues.