Editorial [Intro to the Special Issue on Nonlinear Circuits]

The Special Issue on Nonlinear Circuits includes nine papers and five correspondence items. Given the extremely short lead time between the first announcement and the deadline for submission, this performance demonstrates the vigor of the field. The contents display the variety of problems attacked, the multiplicity of methods used, and the variety of concepts presented. This performance puts to lie all those whose pessimistic thoughts lead them to claim that circuit theory is "dead." All authors deserve a special vote of thanks for their efforts, both in performing their research and in meeting the demands of reviewers and editors.