Atmospheric emissions of greenhouse gases, of which the largest component is carbon dioxide, are highly likely to be causing warming of the atmosphere and global climate change. To reduce those emissions, a variety of mitigation measures have been proposed. A measure that has emerged as favored by many jurisdictions is known as cap-and-trade. In this scheme, an overall limit is placed on atmospheric emissions of one or more greenhouse gases, such as carbon dioxide. Rights to emit portions thereof are assigned to numerous emitters, but these rights are then allowed to be traded among emitters, so that lower-cost emission reducers can abate total emissions with more economic efficiency than higher-cost ones. This course will cover the principles and practice of cap-and-trade and carbon emissions trading.