EXHIBIT 5.1


                         [BARNES & THORNBURG LETTERHEAD]




                                                              September 20, 2001



Vectren Utility Holdings, Inc.
Indiana Gas Company, Inc.
Southern Indiana Gas and Electric Company
Vectren Energy Delivery of Ohio, Inc.
20 N.W. Fourth Street
Evansville, IN 47708

Gentlemen:

     You  have  requested  our  opinion  in  connection  with  the  Registration
Statement  on  Form  S-3  (the  "Registration  Statement")  of  Vectren  Utility
Holdings,  Inc.  (the  "Corporation")  and Indiana Gas Company,  Inc.,  Southern
Indiana  Gas and  Electric  Company and Vectren  Energy  Delivery of Ohio,  Inc.
(individually, a "Guarantor" and collectively, the "Guarantors"), filed pursuant
to the Securities Act of 1933, as amended  ("Securities  Act"),  relating to the
offer and sale by the  Corporation of up to $350,000,000 of debt securities (the
"Debt Securities") and related joint and several guarantees by the Guarantors of
the  Debt  Securities  (the  "Guarantees")  to be  issued  and  sold  under  the
provisions of the Indenture to be entered into between the  Corporation  and the
Guarantors   and  U.S.  Bank  Trust  National   Association,   as  Trustee  (the
"Indenture").  We have examined such records,  certificates  and other documents
and have made  such  investigation  of law as we have  deemed  necessary  in the
circumstances.

     Based on that examination and  investigation,  it is our opinion that, when
the Debt  Securities and  Guarantees  have been issued and sold and the purchase
price for the Debt Securities has been paid in accordance with the  transactions
proposed in the Registration Statement, as the same may be amended, and when the
steps  mentioned in the next paragraph have been taken,  and the Debt Securities
and the Guarantees shall have been duly executed, authenticated and delivered in
accordance with the Indenture,  and delivered against payment therefor, the Debt
Securities will be legal,  valid and binding  obligations of the Corporation and
the  Guarantees  will be legal valid and binding  obligations  of the respective
Guarantors  enforceable against each of them in accordance with their respective
terms subject to (i) the United States Bankruptcy Code,  insolvency,  fraudulent
conveyance,  reorganization,  moratorium and other similar laws now or hereafter
in effect relating to our affecting  creditors' rights or remedies generally and
(ii) general  equitable  principles  (regardless of whether such  enforcement is
considered in a proceeding at law or in equity) and to judicial discretion.

     The steps to be taken which are referred to in the next preceding paragraph
are:





Vectren Utility Holdings, Inc.
Indiana Gas Company, Inc.
Southern Indiana Gas and Electric Company
Vectren Energy Delivery of Ohio, Inc.
September 20, 2001
Page 2


          1. Appropriate  definitive action by the Board of Directors of each of
     the Corporation and the Guarantors or an authorized  committee thereof with
     respect  to  the  proposed  transactions  set  forth  in  the  Registration
     Statement;

          2. Compliance with the Securities Act,  applicable state blue sky laws
     and the Trust Indenture Act of 1939, as amended; and

          3.  Issuance  and  sale  of the  Debt  Securities  and  Guarantees  in
     accordance with the corporate authorization aforesaid.

     This  opinion  letter is limited to the current  Federal laws of the United
States and the current  internal  laws of the State of Indiana  (without  giving
effect to any conflict of law  principles  thereof) and we have not  considered,
and express no opinion on, the laws of any other jurisdiction.

     We consent to the use of our name under the caption "Legal  Matters" in the
Prospectus  included  in the  Registration  Statement  and to the filing of this
opinion as Exhibit 5.1 to the Registration Statement.

                                                      Very truly yours,


                                                      /s/ Barnes & Thornburg

                                                      BARNES & THORNBURG