Pre-financial crisis, interest rate derivatives were widely recognized as a valuable part of the municipal issuer’s financial toolkit.  Post-crisis, they have been a thorn in the side of many issuers, resulting in expensive litigation with failed swap providers – most notably the Lehman and Ambac derivatives trading subsidiaries – and public criticism of municipal issuers said to have fallen prey to more sophisticated providers.  There are several lessons to be learned from the recent spate of litigation, which Orrick covered in an article recently published in The Bond Buyer.