There has been increasing concern over the stack emissions of toxic substances from hazardous waste incinerators, and with improved sampling and analytical technology, measurements are being made at lower and lower levels to support risk assessment and various types of decision-making. However, it is generally difficult to visualize these levels of emissions, which span many orders of magnitude. Data on stack emissions were compiled from various research and compliance testing programs, and representative examples of various types of emissions were plotted on a series of graphs that spans the entire range of concentrations that may be encountered. The result is an illustrative tool for communication as to what emissions from hazardous waste incinerators are actually like.