<DOCUMENT>
<TYPE>EX-99.906CERT
<SEQUENCE>4
<FILENAME>cert906.txt
<DESCRIPTION>906 CERT
<TEXT>
  CERTIFICATION PURSUANT TO RULE 30a-2(b) UNDER THE 1940 ACT AND SECTION 906 OF
                             THE SARBANES-OXLEY ACT

I,  Donald F.  Crumrine,  Director,  Chairman  of the Board and Chief  Executive
Officer of Flaherty & Crumrine  Preferred Income  Opportunity Fund  Incorporated
(the "Registrant"), certify that:

          1.   The Form N-CSR of the Registrant  (the  "Report")  fully complies
               with the requirements of Section 13(a) or 15(d) of the Securities
               Exchange Act of 1934, as amended; and

          2.   The information  contained in the Report fairly presents,  in all
               material  respects,   the  financial  condition  and  results  of
               operations of the Registrant.


Date:    1/29/2008           /s/ Donald F. Crumrine
     -----------------       ---------------------------------------------------
                             Donald F. Crumrine, Director, Chairman of the Board
                             and Chief Executive Officer
                             (principal executive officer)


I, R. Eric Chadwick,  Chief Financial Officer,  Treasurer, and Vice President of
Flaherty  &  Crumrine   Preferred  Income  Opportunity  Fund  Incorporated  (the
"Registrant"), certify that:

          1.   The Form N-CSR of the Registrant  (the  "Report")  fully complies
               with the requirements of Section 13(a) or 15(d) of the Securities
               Exchange Act of 1934, as amended; and

          2.   The information  contained in the Report fairly presents,  in all
               material  respects,   the  financial  condition  and  results  of
               operations of the Registrant.


Date:    1/29/2008               /s/ R. Eric Chadwick
     -------------------         -----------------------------------------------
                                 R. Eric Chadwick, Chief Financial Officer,
                                 Treasurer, and Vice President
                                 (principal financial officer)


</TEXT>
</DOCUMENT>
