Morgan, Lewis & Bockius LLP
1111 Pennsylvania Avenue, N.W.
Washington, D.C.  20004


September 7, 2007


VIA EDGAR

U.S. Securities and Exchange Commission
100 F Street, N.E.
Washington, D.C. 20549

Re:      Rydex ETF Trust (File Nos. 333-101625 and 811-21261)
         ----------------------------------------------------

Ladies and Gentlemen:

On behalf of Rydex  ETF Trust  (the  "Trust")  we are  filing,  pursuant  to the
Securities  Exchange  Act of 1934 and the  Investment  Company  Act of  1940,  a
definitive Schedule 14A, notice,  proxy statement and form of voting instruction
for a Special Meeting of  Shareholders  ("Meeting") of the Trust scheduled to be
held on or about October 4, 2007.

The  Meeting  is  being  called  for the  purposes  of  approving  new  advisory
agreements between PADCO Advisors, Inc. and Rydex Series Funds and Rydex Dynamic
Funds and PADCO  Advisors II, Inc. and Rydex Variable Trust and Rydex ETF Trust,
as well as a new sub-advisory  agreement between PADCO Advisors II, Inc. and CLS
Investment Firm, LLC. It is anticipated that the current investment advisory and
sub-advisory agreements will terminate if and when a change of control occurs in
Rydex  Holdings,  Inc.,  the parent  company of PADCO  Advisors,  Inc. and PADCO
Advisors II, Inc.,  resulting from the transfer of ownership of Rydex  Holdings,
Inc. to  Security  Benefit  Corporation  and  Security  Benefit  Life  Insurance
Company.

The Trust intends to mail definitive proxy materials to shareholders on or about
September  6, 2007.  Please  feel free to contact me at  202.739.5684  with your
questions or comments.

Sincerely,


/s/ Laura E. Flores
-------------------
Laura E. Flores