SIFMA provides comments to the Securities and Exchange Commission (SEC) on a temporary rule regarding principal trades with certain advisory clients, File No. S7-23-07; Release No. IA-3118.  The proposal would amend rule 206(3)-3T under the Investment Advisers Act of 1940 (Rule) to extend the date on which the Rule will sunset from December 31, 2010 to December 31, 2012.  SIFMA strongly supports the extension of the Rule for an additional period of two years beyond its currently scheduled expiration date. The extension should provide the time necessary for the SEC to figure out how to best incorporate principal trading relief into a harmonized standard of care for brokers and advisers, as required by Section 913 of Dodd-Frank Act.