11-K

                                  UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549


                                    FORM 11-K




(Mark One)

[X]  ANNUAL REPORT  PURSUANT TO SECTION 15(d) OF THE SECURITIES  EXCHANGE ACT OF
     1934

For the fiscal year ended December 31, 2001

                                       OR

[ ] TRANSITION  REPORT  PURSUANT TO SECTION 15(d) OF THE SECURITIES  EXCHANGE
    ACT OF 1934

For the transition period from                     to
                               ------------------     ------------------



                         Commission File Number 1-11377




                   CINERGY CORP. UNION EMPLOYEES' 401(k) PLAN
                            (Full title of the plan)






                                  CINERGY CORP.
          (Name of issuer of the securities held pursuant to the plan)





                             139 East Fourth Street
                             Cincinnati, Ohio 45202
                    (Address of principal executive offices)




                         Cinergy Corp. Union Employees'
                                   401(k) Plan

                   Index to Financial Statements and Exhibits


                                                                       Page No.
                                                                       --------

(a)  Financial Statements

      Report of Independent Public Accountants                           3

      Statements of Net Assets Available for Benefits
       as of December 31, 2001 and 2000                                  4

      Statement of Changes in Net Assets Available for Benefits
       for the Year Ended December 31, 2001                              5

      Notes to Financial Statements                                     6-10

      Financial Statement Schedule (As Required By The Employee
       Retirement Income Security Act of 1974):

      Schedule I - Schedule of Assets Held at End of Year
       as of December 31, 2001                                           11



(b)  Exhibit 23 - Consent of Independent Public Accountants

(c)  Exhibit 99 - Confirmation Letter of Receipt of Certain
     Representations from Arthur Andersen LLP




Report of Independent Public Accountants
- ----------------------------------------


To the Plan Administrator of the
Cinergy Corp. Union Employees' 401(k) Plan:

We have audited the accompanying statements of net assets available for benefits
of the CINERGY CORP. UNION EMPLOYEES'  401(k) PLAN (the Plan) as of December 31,
2001 and 2000, and the related  statement of changes in net assets available for
benefits for the year ended December 31, 2001.  These  financial  statements and
the schedule referred to below are the  responsibility of the Plan's management.
Our  responsibility  is to express an opinion on these financial  statements and
the schedule based on our audits.

We conducted our audits in accordance with auditing standards generally accepted
in the United States. Those standards require that we plan and perform the audit
to obtain reasonable  assurance about whether the financial  statements are free
of material misstatement. An audit includes examining, on a test basis, evidence
supporting  the amounts and  disclosures in the financial  statements.  An audit
also includes assessing the accounting principles used and significant estimates
made by  management,  as well as  evaluating  the  overall  financial  statement
presentation.  We believe  that our audits  provide a  reasonable  basis for our
opinion.

In our opinion,  the financial  statements  referred to above present fairly, in
all material  respects,  the net assets available for benefits of the Plan as of
December  31,  2001,  and 2000,  and the  changes  in net assets  available  for
benefits for the year ended  December  31, 2001 in  conformity  with  accounting
principles generally accepted in the United States.

Our audits  were  performed  for the  purpose of forming an opinion on the basic
financial statements taken as a whole. The supplemental schedule (Schedule I) is
presented for the purpose of  additional  analysis and is not a required part of
the basic financial statements but is supplementary  information required by the
Department of Labor Rules and Regulations for Reporting and Disclosure under the
Employee  Retirement  Income Security Act of 1974. The supplemental  schedule is
the responsibility of the Plan's management.  The supplemental schedule has been
subjected  to the  auditing  procedures  applied  in  the  audits  of the  basic
financial  statements  and, in our  opinion,  is fairly  stated in all  material
respects in relation to the basic financial statements taken as a whole.



                                                             ARTHUR ANDERSEN LLP


Indianapolis, Indiana,
May 20, 2002.



                   Cinergy Corp. Union Employees' 401(k) Plan

                 Statements of Net Assets Available for Benefits
                        As of December 31, 2001 and 2000


                                                                December 31,
                                                         2001            2000
ASSETS:
   Investments, at fair value (see Notes 3 and 4)  $102,878,176     $100,692,504

   Employer's contribution receivable                   982,968        1,247,167
                                                        -------        ---------

         Net assets available for benefits         $103,861,144     $101,939,671
                                                   ============     ============



The accompanying notes and schedule are an integral part of these statements.


                   Cinergy Corp. Union Employees' 401(k) Plan

            Statement of Changes in Net Assets Available for Benefits
                      For the Year Ended December 31, 2001


ADDITIONS:
   Additions to net assets attributed to:
     Investment (loss) income:
       Net depreciation in fair value of
         investments (see Notes 3 and 4)                           $ (7,501,848)
       Interest and dividends                                         3,829,354
                                                                      ---------
                                                                     (3,672,494)

     Contributions:
       Participant                                                    6,709,933
       Employer                                                       2,957,404
       Rollover                                                         100,901
                                                                        -------
                                                                      9,768,238
                                                                      ---------
                  Total additions                                     6,095,744

DEDUCTIONS:
    Deductions from net assets attributed to:
       Benefits paid to participants                                 (3,152,658)
                                                                     ----------
                  Total deductions                                   (3,152,658)
                                                                     ----------

Net increase prior to transfers                                       2,943,086
Interplan transfers (See Note 2)                                     (1,021,613)
                                                                     ----------
                                                                      1,921,473

Net assets available for benefits:
Beginning of year                                                   101,939,671
                                                                    -----------
End of year                                                        $103,861,144
                                                                   ============


The accompanying notes and schedule are an integral part of these statements.

                   Cinergy Corp. Union Employees' 401(k) Plan

                          Notes to Financial Statements
                           December 31, 2001 and 2000

(1)  Plan Description-
     -----------------

     The following description of the Cinergy Corp. Union Employees' 401(k) Plan
     (the Plan) provides only general information.  Participants should refer to
     the Plan Document for a more complete description of the Plan's provisions.

     (a)  General--The  Plan  is a  defined  contribution  plan  covering  union
          -------
          employees of Cinergy Corp.'s subsidiaries (collectively,  the Company)
          represented by the  International  Brotherhood of Electrical  Workers,
          Local 1393. The Plan is administered by the Cinergy Benefits Committee
          and trusteed by the Fidelity Management Trust Company (Fidelity).  The
          Plan is subject to the  provisions of the Employee  Retirement  Income
          Security Act of 1974 (ERISA), as amended. The administrative  expenses
          of the Plan are paid by the Company.

          Effective  January  1,  2000,  the  Plan was  amended  to  modify  the
          definition  of a change in  control  of the  Company.  This  amendment
          conforms  the  plan   document  to  a  standard   definition  of  what
          constitutes  a change in  control by  reducing  the  concentration  of
          voting  power  held by any one  person or group  from more than 50% to
          more than 20%. Also, this amendment clarifies the sources available to
          the Company for  contributing the employer match to the Cinergy Common
          Stock Fund (i.e.  authorized  and/or  unissued shares of common stock,
          treasury stock, etc.).  Finally,  this amendment provides that payroll
          deductions  that  are  used to  repay a  participant  loan may only be
          stopped under an order from a Federal Bankruptcy Court.

          Effective  January 1, 2000, the Plan was amended to permit the Company
          to automatically  enroll new full time employees eligible for the Plan
          at a 1%  deferral  rate.  The  contributions  made to the  plan on the
          employee's  behalf will be  invested in one or more funds  selected in
          accordance with procedures  established by the plan administrator.  If
          an employee chooses not to participate,  Fidelity,  the  recordkeeper,
          must be contacted by the employee to change the deferral rate to 0%.

          Effective  January 1, 2001,  the Plan was further  amended to increase
          the 1% tax contribution for automatic enrollment to 3%.

     (b)  Contributions--Under  the Plan,  participants may contribute up to 15%
          -------------
          of annual pre-tax  compensation,  as defined in the Plan document.  In
          addition,  a participant may make after-tax  contributions to the Plan
          which, when combined with pre-tax contributions, may not exceed 15% of
          base pay. Pre-tax and after-tax  contributions  are subject to certain
          limitations.  The pre-tax and after-tax  contributions are invested by
          the  trustee,  as  directed  by  each  participant,  in  one  or  more
          investment funds, including the Cinergy Common Stock Fund.

          The  Company  matches 60% of the first 5% of base pay  contributed  by
          each  participant.  An additional  incentive match of up to 40% of the
          first 5% of base pay that a participant contributes may be contributed
          at the  discretion  of the  Company's  Board of  Directors.  For those
          employees who do not contribute to the Plan,  the Company  contributes
          an incentive  match assuming the employee  contributed 1% of base pay.
          All employer  contributions are invested by the trustee in the Cinergy
          Common Stock Fund. The employer  contributions  must remain in Cinergy
          Common Stock Fund until the  participant  reaches age 50 and are shown
          in Note 3 as  "Non-participant  Directed"  funds  until  the  employee
          elects to transfer the funds to another investment option.

     (c)  Vesting--Participants  are immediately vested in all contributions and
          -------
          earnings thereon.

     (d)  Participant  Account--Each  participant's account is credited with the
          --------------------
          participant's   contribution   and   allocation   of   the   Company's
          contribution   and  plan  earnings.   Allocations  are  based  on  the
          participant's account balance or contribution percentage as defined in
          the plan  document.  The benefit to which a participant is entitled is
          the  benefit  that  can be  provided  from  the  participant's  vested
          account.

          A  participant  may  elect  to  change  investment  funds  and/or  the
          contribution allocation percentage among funds at any time.

     (e)  Payment of  Benefits--Participants  are generally  eligible to receive
          --------------------
          distributions  of assets from the Plan upon  termination of employment
          including retirement, death, or disability.  Distributions are paid in
          a lump sum for vested  benefits of $5,000 or less.  Distributions  are
          paid in a lump sum or up to ten annual  installments  (at the election
          of the participant)  for vested benefits  greater than $5,000.  Active
          participants are also eligible to apply to the Plan  administrator for
          "hardship"  withdrawals  from their pretax account in accordance  with
          Plan provisions.

     (f)  Participant  Loans--Subject to certain  limitations,  participants may
          ------------------
          apply for loans from their pre-tax account  balances.  Interest on the
          loans is set at the  prime  rate  plus 50 basis  points at the time of
          borrowing,   and  the  loans  are   secured  by  the  balance  in  the
          participant's account. Loans are to be repaid within 54 months through
          regular payroll deductions.

(2)  Significant Accounting Policies-
     --------------------------------

     (a)  Basis of Accounting--The accompanying financial statements of the Plan
          -------------------
          are prepared on an accrual basis.

     (b)  Investment Valuation and Income Recognition--Investments are stated at
          -------------------------------------------
          fair value.  Shares of registered  investment  companies are valued at
          quoted redemption prices which represent the net asset value of shares
          held by the Plan at  year-end.  Cinergy  common stock is valued at its
          quoted  market  price.  Participant  loans are  valued at cost,  which
          approximates fair value.

          Purchases and sales of securities are recorded on a trade-date  basis.
          Interest  income is  recorded  on the  accrual  basis.  Dividends  are
          recorded on the ex-dividend date.

          Transfers  of assets  between the Plan,  the Cinergy  Corp.  Non-Union
          Employees' 401(k) Plan and the Cinergy Corp. Union Employees'  Savings
          Incentive Plan occur as a result of changes in employee status between
          the   union    classification    and   the   exempt   and   non-exempt
          classifications.  Such transfers are reflected as interplan  transfers
          on the statement of changes in net assets available for benefits.

     (c)  Use  of   Estimates--The   preparation  of  financial   statements  in
          -------------------
          conformity with accounting principles generally accepted in the United
          States  requires  management to make  estimates and  assumptions  that
          affect the  reported  amounts of assets and  liabilities  and  changes
          therein,  and disclosure of contingent  assets and  liabilities at the
          date of the  financial  statements.  Actual  results could differ from
          those estimates.

     (d)  Payments of Benefits--Benefit payments are recorded when paid.
          --------------------


(3)  Non-participant Directed Investments-
     -------------------------------------

     Information  about the net assets  and the  significant  components  of the
     changes in net assets relating to  non-participant  directed balances is as
     follows:
                                                  December  31,
                                                 -------------
                                               2001          2000
                                               ----          ----
       Net  assets:
         Cinergy  Common  Stock Fund       $30,140,842    $28,317,718
                                           ===========    ===========


                                                             Year Ended
                                                          December 31, 2001
                                                          -----------------
        Changes in net assets:
          Contributions                                         $2,957,404
          Dividends                                              1,464,876
          Net depreciation                                      (1,199,680)
          Benefits paid to participants                           (516,091)
          Transfers to participant-directed investments           (510,644)
          Interplan transfers                                     (372,741)
                                                                  --------
                                                                $1,823,124
                                                                ==========

(4)  Investments-
     ------------

     The fair value of individual  investments  that represent 5% or more of the
     Plan's net assets  available  for benefits as of December 31, 2001 and 2000
     are as follows:

                                                     2001              2000
                                                     ----              ----

      *Cinergy Common Stock Fund                  $41,862,916       $40,361,619
       Fidelity Magellan Fund                      25,369,811        26,990,547
       Fidelity Equity-Income Fund                 12,768,858        13,049,853
       Fidelity Retirement Money Market Fund        7,641,950         6,528,109

     * $30,140,842 is non-participant directed funds.

     During  2001,  the  Plan's  investments  (including  gains  and  losses  on
     investments  bought and sold, as well as held during the year)  depreciated
     in value by $7,501,848 as follows:

                                  Mutual funds               $5,713,224
                                  Common stock                1,788,624
                                                              ---------
                                                             $7,501,848
                                                             ==========

(5)  Federal Income Tax Status-
     --------------------------

     The Internal Revenue Service has determined and informed the Plan by letter
     dated  June 26,  2000,  that the Plan and  related  trust are  designed  in
     accordance with applicable sections of the Internal Revenue Code (IRC). The
     Plan has been amended since receiving the  determination  letter.  However,
     the Plan administrator  believes the Plan is designed and is being operated
     in compliance with the applicable requirements of the IRC.

(6)  Plan Termination-
     -----------------

     Although  it has not  expressed  any intent to do so, the  Company  has the
     right under the Plan to discontinue  its  contributions  at any time and to
     terminate the Plan subject to the provisions of ERISA.

(7)  Related Party Transactions-
     ---------------------------

     Certain Plan  investments  are shares of mutual funds  managed by Fidelity.
     Fidelity  is the  Trustee  as  defined  by the  Plan and  therefore,  these
     transactions qualify as party-in-interest  transactions. The Cinergy Common
     Stock Fund  holds  common  stock of the  Company as defined by the Plan and
     therefore, these transactions qualify as party-in-interest transactions.

(8)  Investment Risk-
     ----------------

     Investment  securities,  in general,  are exposed to various risks, such as
     interest rate, credit an overall market volatility risks.  Further,  due to
     the level of risk  associated  with certain  investment  securities,  it is
     reasonably  possible  that changes in the values of  investment  securities
     will occur in the near term and that such changes could  materially  affect
     the amounts reported in the accompanying statements of net assets available
     for benefits.


(9)  Subsequent Event
     ----------------

     Effective  January 1, 2002,  the Plan was  restated to allow the portion of
     the Plan that is held at any one time in the Cinergy  Common  Stock Fund to
     be designated  as an Employee  Stock  Ownership  Plan within the meaning of
     Section  4975(e)(7)  of the code  designed to invest  primarily  in Cinergy
     Corp.  stock and is intended to qualify under Section 401(a) of the Code as
     a stock bonus plan.

     In  addition,  the  portion of the Plan that at any one time is not held in
     the Cinergy  Common  Stock Fund is a profit  sharing  plan for  purposes of
     Section 401(a)(27)(B) of the Code that is intended to qualify under Section
     401(a).  This profit  sharing plan includes a cash or deferred  arrangement
     intended to qualify under Section 401(k) of the Code.

                                                                                                                       Schedule I
                                                    Cinergy Corp. Union Employees'
                                                              401(k) Plan

                                                            EIN: 31-1385023
                                                           Plan Number: 101

                                  Schedule H, Part IV, Line 4i--Schedule of Assets Held at End of Year
                                                        As of December 31, 2001


   Identity of Issuer, Borrower,        Description of Investment, Including Maturity Date, Rate of Interest,              Current
     Lessor, or Similar Party                           Collateral and Par or Maturity Value                  Cost          Value
     ------------------------                           ------------------------------------                  ----          -----

*   Cinergy Corp.                               Common Stock Fund                                      $33,993,478       $41,862,916
*   Fidelity Investments                        Magellan Fund                                                   **        25,369,811
*   Fidelity Investments                        Equity-Income Fund                                              **        12,768,858
*   Fidelity Investments                        U.S. Bond Index Fund                                            **         1,496,209
*   Fidelity Investments                        Diversified International Stock Fund                            **         1,035,807
*   Fidelity Investments                        Low-Priced Stock Fund                                           **         1,362,828
*   Fidelity Investments                        Freedom Income Fund                                             **           162,790
*   Fidelity Investments                        Freedom 2000 Fund                                               **           456,755
*   Fidelity Investments                        Freedom 2010 Fund                                               **         1,941,639
*   Fidelity Investments                        Freedom 2020 Fund                                               **           758,400
*   Fidelity Investments                        Freedom 2030 Fund                                               **           446,870
*   Fidelity Investments                        Freedom 2040 Fund                                               **            60,903
    Franklin Investments                        Blue Chip Fund                                                  **         1,742,647
*   Fidelity Investments                        Spartan U.S. Equity Index Fund                                  **           567,619
*   Fidelity Investments                        Small Mid-Cap Growth Fund                                       **         1,498,146
*   Fidelity Investments                        Retirement Money Market Fund                                    **         7,641,950
*   Various Plan Participants                   Participant Loans (interest rates ranging from 7.00-10.50%)     **         3,704,027
        Total assets held at end of year                                                                                $102,878,176
*   Denotes a party-in-interest
**  Cost omitted for participant directed investments


                                                                     Schedule II


                                   SIGNATURES




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



                         CINERGY CORP. UNION EMPLOYEES'
                                   401(K) PLAN
                                   -----------


                              By /s/ DARLENE HUGHES
                              ---------------------
                                 Darlene Hughes
                               Plan Administrator




May 31, 2002

                                                                      EXHIBIT 23






                    CONSENT OF INDEPENDENT PUBLIC ACCOUNTANTS



As independent  public  accountants,  we hereby consent to the  incorporation by
reference of our report dated May 20, 2002 included in the Annual Report on Form
11-K for the year ended December 31, 2001 of the Cinergy Corp.  Union Employees'
401(k) Plan, into Cinergy Corp.'s previously filed  Registration Statements File
No. 33-56067 and 333-72900.




                                                             ARTHUR ANDERSEN LLP

Indianapolis, Indiana
May 31, 2002.

EX-99

                                                                      EXHIBIT 99




May 31, 2002

Office of the Chief Accountant
Securities and Exchange Commission
Mail Stop 11-3
450 Fifth Street, N.W.
Washington, D.C.  20549


Dear Sir/Madam:

The registrant has received from Arthur Andersen LLP ("AA") an assurance letter,
dated May 31, 2002,  representing  that the audit  performed with respect to the
financial  statements of the registrant for the year ended December 31, 2001 was
subject to adequate quality control systems and included appropriate  continuity
of AA personnel and availability of its national office consultation.



Very truly yours,

Darlene Hughes
/s/ DARLENE HUGHES
Darlene Hughes, Plan Administrator