SECURITIES
                             AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549

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                                    FORM 8-K

                                 CURRENT REPORT



                     PURSUANT TO SECTION 13 OR 15(D) OF THE
                         SECURITIES EXCHANGE ACT OF 1934

                        Date of Report: DECEMBER 31, 2006
                        (Date of earliest event reported)



                         PRINCIPAL FINANCIAL GROUP, INC.
             (Exact name of registrant as specified in its charter)


        DELAWARE                       1-16725                 42-1520346
(State or other jurisdiction    (Commission file number)     (I.R.S. Employer
    of incorporation)                                    Identification Number)


                     711 HIGH STREET, DES MOINES, IOWA 50392
                    (Address of principal executive offices)

                                 (515) 247-5111
              (Registrant's telephone number, including area code)

Check  the  appropriate  box  below  if the  Form  8-K  filing  is  intended  to
simultaneously  satisfy the filing obligation of the registrant under any of the
following provisions:

[ ] Written communications pursuant to Rule 425 under the Securities Act (17 CFR
    230.425)
[ ] Soliciting  material pursuant to Rule 14a-12 under the Exchange Act (17  CFR
    240.14a-12)
[ ] Pre-commencement  communications  pursuant  to  Rule 14d-2(b) under the
    Exchange Act (17 CFR 240.14d-2(b))
[ ] Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange
    Act (17 CFR 240.13e-4(c))

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ITEM 7.01         REGULATION FD DISCLOSURE

Principal  Financial  Group,  Inc.  (NYSE:  PFG)  today  announced  that  it has
completed the acquisition of WM Advisors,  Inc. and its subsidiaries,  effective
December 31, 2006, from Washington Mutual,  Inc. (NYSE:WM).


                                    SIGNATURE


Pursuant  to the  requirements  of the  Securities  Exchange  Act of  1934,  the
registrant  has duly  caused  this  report  to be  signed  on its  behalf by the
undersigned thereunto duly authorized.


                                    PRINCIPAL FINANCIAL GROUP, INC.


                                    By:    /S/THOMAS J. GRAF
                                          --------------------------------------
                                    Name:  Thomas J. Graf
                                    Title: Senior Vice President - Investor
                                           Relations

Date:    December 31, 2006



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