Exhibit 10.1

SUPPLEMENTAL RETIREMENT PLAN AGREEMENT
[Form for W.D. Harvey, E.G. Protsch, B.J. Swan]

        This Supplemental Retirement Plan Agreement is made this ____ day of ____________, 2008, by and between [insert name] (the "Officer") and Alliant Energy Corporation (the "Company").

W I T N E S S E T H :

         WHEREAS, Alliant Energy wishes to provide supplemental retirement benefits to a select group of senior executive personnel, including the Officer, to ensure the overall effectiveness of the Company’s executive compensation program and that the Company will be able to attract, retain, and motivate qualified senior executive personnel;

         WHEREAS, the Company and the Officer have heretofore entered into a Supplemental Retirement Plan Agreement (the "Prior Agreement") providing supplemental retirement, deferred compensation or similar benefits; and

         WHEREAS, the Company and the Officer wish to enter into this Agreement, which shall amend, restate, supersede and replace the Prior Agreement;

         NOW, THEREFORE, the parties agree as follows:

ARTICLE I

SCOPE OF AGREEMENT

         1.1     Effect on Prior Agreement . This Agreement shall supersede and replace the Prior Agreement, effective as of the date of this Agreement, and the parties shall thereafter have no further rights or obligations under the Prior Agreement.

         1.2     Effect on Change of Control Agreements . If the Officer is a party to an agreement which is binding on the Company and which takes effect in the event of a change in control, such agreement shall supersede and control over the provisions of this Agreement in the event of any conflict between the two.

         1.3     No Contract of Employment . This Agreement does not constitute an employment agreement between the Officer and the Company. Nothing in this Agreement shall affect the Company’s right to terminate the Officer’s employment or position as an officer at any time, with or without cause.

         1.4     Effect on Other Benefits . Nothing in this Agreement shall modify, impair or otherwise affect the rights of the Officer to participate in or receive benefits under any other employee benefit plan of the Company, it being understood that the rights of the Officer to participate in or receive benefits under any such plan shall be determined in accordance with the provisions of such plan and shall not be affected by the provisions of this Agreement.

ARTICLE II

DEFINITIONS

         2.1     Beneficiary means the beneficiary or beneficiaries designated in writing by the Officer on the form provided in Appendix A or, in default of such designation or the failure of any designated beneficiary to survive the Officer, the Officer’s estate.

         2.2     Board of Directors means the Board of Directors of Alliant Energy Corporation, the Compensation and Personnel Committee of the Board, or any committee of the Board which is designated by the Board of Directors, or permitted by the Bylaws of the Alliant Energy Corporation, to act on behalf of the Board of Directors.

         2.3     Cause means, but is not limited to, (i) embezzlement of funds of the Company or any affiliate; (ii) fraud; and (iii) acts that cause harm to the Company or an affiliate or to the reputation thereof.

         2.4     Continuous Employment means the Officer’s last continuous period of employment with the Company immediately preceding the Officer’s Retirement. If the Officer has been continuously employed by the Company since the merger of IES Industries Inc., WPL Holdings, Inc. and Interstate Power Company, the Officer’s Continuous Employment shall also include his or her last continuous period of employment with IES Industries Inc., WPL Holdings, Inc. or Interstate Power Company, immediately preceding the date of such merger.

         2.5     Code means the Internal Revenue Code of 1986, as amended.

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         2.6     Dependent Child or Children means any child of the Officer who, on the date of the applicable payment to such child under this Agreement, is 18 years of age or under, is 24 years of age or under and is a "student" as defined in Code Section 151(c)(4), or is a "substantially handicapped person." The term "child" includes any naturally born or legally adopted child; provided, in the case of an adopted child, that the adoption became final prior to such child’s 18th birthday. The term "substantially handicapped person" includes any person who has a "physical or mental impairment which substantially limits one or more major life activities," as those terms are defined in 29 C.F.R. Section 32.3.

         2.7     Disabled means the Officer has satisfied (and continues to satisfy) the requirements for receiving disability benefits under the terms of the Company’s long-term disability plan and is unable to engage in any substantial gainful activity by reason of any medically determinable physical or mental impairment that can be expected to result in death or can be expected to last for a continuous period of not less than 12 months.

         2.8     Earnings means the Officer’s base salary, bonus and/or annual incentive pay for personal services rendered to the Company. The Officer’s base salary shall be treated as Earnings in the period in which it would have been payable, regardless of any deferral elections. The Officer’s bonus and/or annual incentive pay shall be treated as Earnings in the calendar year in which it is earned, regardless of when it is paid.

         2.9     Eligible Officer means Chairman, Chief Executive Officer, President or Executive Vice President of the Company.

         2.10     Final Average Earnings means the Officer’s average monthly Earnings for the three consecutive calendar years out of the Officer’s last ten completed calendar years of employment with the Company that yields the highest average.

         2.11     Normal Retirement Date means the later of the Officer’s 62nd birthday or the date on which the Officer completes ten years of Continuous Employment.

         2.12     Pension Plan means any and all of the following plans from which the Officer is entitled to a benefit:

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         2.13     Retirement and/or Retires means the Officer’s Separation from Service after the Officer has satisfied the requirements under either Article III or Article IV. An Officer shall not have a Retirement if the Separation from Service is imposed by the Company for Cause, whether before or after the Officer has satisfied the age and/or service requirements of Article III or Article IV.

         2.14     Separation from Service means an Officer’s termination of employment with Alliant Energy Corporation or, if the Participant continues to provide services following such termination, such later date as is considered a separation from service from the Company and its 409A affiliates within the meaning of Code Section 409A. Specifically, if a Participant continues to provide services to the Company or a 409A affiliate in a different capacity (e.g., a former employee becomes a director or an independent contractor), such shift in status is not automatically a Separation from Service, subject to Treas. Reg. section 1.409A-1(h)(5) among other provisions. For purposes of this Agreement, an Officer’s termination of employment shall occur when the Company and the Officer reasonably anticipate that no further services will be performed by the Officer for the Company and its 409A affiliates (whether as an employee, a director or an independent contractor) or that the level of bona fide services the Officer will perform after such date will permanently decrease to no more than 20% of the average level of bona fide services performed by the Officer (whether as an employee, director or independent contractor) for the Company and its 409A affiliates over the immediately preceding 36-month period (or such lesser period of services). Notwithstanding the foregoing, if an Officer takes a leave of absence for purposes of military leave, sick leave or other bona fide leave of absence, the Officer will not be deemed to have incurred a termination of employment for the first 6 months of the leave of absence, or if longer, for so long as the Officer’s right to reemployment is provided either by statute or by contract; provided that if the leave of absence is due to a medically determinable physical or mental impairment that can be expected to result in death or last for a continuous period of not less than 6 months, where such impairment causes the Officer to be unable to perform the duties of his or her position of employment or any substantially similar position of employment, the leave may be extended for up to 29 months without causing a termination of employment. For purposes of this Agreement, the term "409A affiliate" means each entity that is required to be included in the Company’s controlled group of corporations within the meaning of Code Section 414(b), or that is under common control with the Company within the meaning of Code Section 414(c), provided, however, that the phrase "at least 50 percent" shall be used in place of the phrase "at least 80 percent" each place it appears therein or in the regulations thereunder.

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         2.15     Supplemental Benefit means the benefit described in Section 3.1 and payable to the Officer pursuant to Articles III, IV or V.

         2.16     Surviving Spouse means the individual, if any, who is legally married to the Officer at the time of the Officer’s death.

ARTICLE III

NORMAL RETIREMENT BENEFIT

         3.1    Supplemental Benefit .

        (a)     Subject to the following provisions of this Article III and Section 7.1, if the Officer remains a full-time employee, remains an Eligible Officer until his or her Normal Retirement Date, and subsequently Retires, the Officer shall receive a Supplemental Benefit equal to 60% of the Officer’s Final Average Earnings, reduced by the sum of the monthly benefits payable to the Officer from all of the Pension Plans.

        (b)     For the purposes of Section 3.1(a), the amount of the Officer’s monthly benefit from each applicable Pension Plan shall be determined as follows:

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        (c)     The Supplemental Benefit shall be paid at the same time and in the same form as the benefits the Officer is entitled to receive from the Pension Plans that are nonqualified deferred compensation arrangements. The applicable rules are as follows:

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       3.2     Officer’s Death After Retirement .

        (a)     If the Officer dies after receiving at least 144 monthly Supplemental Benefit payments pursuant to Section 3.1(c)(i)(A), the Officer’s Supplemental Benefit shall terminate upon the Officer’s death (with the full monthly payment being made for the month in which such death occurs), and the Company shall have no further obligation to make any payments under this Section 3.2(a).

        (b)     If the Officer dies after the commencement of Supplemental Benefit payments pursuant to Section 3.1(c)(i)(A) but prior to receiving 144 monthly payments, the Officer’s Surviving Spouse (if any) shall continue to receive the amount of the monthly payments paid to the Officer for the month prior to death until the date on which the Officer and such Surviving Spouse have received a total of 144 monthly payments. If both th