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


                                  SCHEDULE 13G



                   Under the Securities Exchange Act of 1934
                             (Amendment No._____)*


                              Herman Miller, Inc.
- --------------------------------------------------------------------------------
                                (Name of Issuer)

                                 Common Stock
- --------------------------------------------------------------------------------
                         (Title of Class of Securities)

                                   600544100
                        ------------------------------
                                 (CUSIP Number)


Check the following box if a fee is being paid with this statement [X]. (A fee 
is not required only if the filing person: (1) has a previous statement on file 
reporting beneficial ownership of more than five percent of the class of 
securities described in Item 1; and (2) has filed no amendment subsequent 
thereto reporting beneficial ownership of five percent or less of such class.)
(See Rule 13d-7).

*The remainder of this cover page shall be filled out for a reporting person's
initial filing on this form with respect to the subject class of securities, and
for any subsequent amendment containing information which would alter the
disclosures provided in a prior cover page.

The information required in the remainder of this cover page shall not be deemed
to be "filed" for the purpose of Section 18 of the Securities Exchange Act of
1934 ("Act") or otherwise subject to the liabilities of that section of the Act
but shall be subject to all other provisions of the Act (however, see the
Notes).




SEC 1745 (10-88)

<PAGE>
 

  CUSIP NO. 600544100                                   Page  2  of  5  Pages
           -----------                                       ---    ---
 
- ------------------------------------------------------------------------------
      NAMES OF REPORTING PERSONS.
 1    S.S. OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSONS.
        ARIEL CAPITAL MANAGEMENT, INC.                  John W. Rogers, Jr.
        IRS ID # 36-3219058                             SSN # 360-52-3254
                          
- ------------------------------------------------------------------------------
      CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP* 
 2      Not Applicable                                          (a) [_]
                                                                (b) [_]
                                                 
- ------------------------------------------------------------------------------
      SEC USE ONLY
 3
 

- ------------------------------------------------------------------------------
      CITIZENSHIP OR PLACE OF ORGANIZATION
 4                                 
        Illinois Corporation

- ------------------------------------------------------------------------------
                          SOLE VOTING POWER
                     5                                                       
     NUMBER OF              Ariel - 4,300,220                     Rogers - 0
 
      SHARES       -----------------------------------------------------------
                          SHARED VOTING POWER
   BENEFICIALLY      6       
                            Ariel - 0                             Rogers - 0
     OWNED BY
                   -----------------------------------------------------------
       EACH               SOLE DISPOSITIVE POWER
                     7       
    REPORTING               Ariel - 4,355,420                     Rogers - 0
 
      PERSON       -----------------------------------------------------------
                          SHARED DISPOSITIVE POWER
       WITH          8       
                            Ariel - 0                             Rogers - 0
- ------------------------------------------------------------------------------
      AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
 9                           
                            Ariel - 4,355,420                     Rogers - 0
- ------------------------------------------------------------------------------
      CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES*
10                      
                                                                    [_]
        Not Applicable
- ------------------------------------------------------------------------------
      PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)
11           
                            Ariel - 4,355,420/79,567,818 = 5.47%  Rogers - 0%

- ------------------------------------------------------------------------------
      TYPE OF REPORTING PERSON*                  
12           
                            Ariel - IA                            Rogers - HC

- ------------------------------------------------------------------------------
                     *SEE INSTRUCTIONS BEFORE FILLING OUT!
*  This report is being made on behalf of John W. Rogers, Jr., President and 
principal shareholder of Ariel Capital Management, Inc., who may be deemed to 
have beneficial ownership of the securities of the issuer. Mr. Rogers disclaims 
Beneficial Ownership of Shares held by Ariel Capital Management, Inc.

<PAGE>

                                                          Date:      4/30/99
                                                                 ---------------
                                                                   Page 3 of 5
 
Item 1 (a)     Name of Issuer

                 Herman Miller, Inc.
               --------------------

Item 1 (b)      Address of Issuer's Principal Executive Offices

                855 East Main Avenue; Zeeland, MI 49464-0302
               ---------------------------------------------

Item 2 (a)     Name of Person Filing

                 Ariel Capital Management, Inc.
               ----------------------------------------

Item 2 (b)     Address of Principal Business Office 

                 307 North Michigan Avenue, Chicago, IL 60601
               -------------------------------------------------------

Item 2 (c)     Citizenship

                 an Illinois corporation
               ----------------------------------------

Item 2 (d)     Title of Class of Securities

                 Common Stock
               ----------------------------------------

Item 2 (e)     CUSIP Number:

                 600544100
               ----------------------------------------

Item 3.        This statement is filed pursuant to 13d-1 (b) or 13d-2 (b) and
               the person filing is an investment adviser registered under
               section 203 of the Investment Advisers Act of 1940.


Item 4.        Ownership.

               (a)  Amount Beneficially Owned:

                    (See Page 2, No. 9)
               ----------------------------------------

<PAGE>

                                                          Date:      4/30/99
                                                                 ---------------
                                                                   Page 4 of 5

 

     (b)  Percent of class:  

                (See Page 2, No. 11)
          ----------------------------

     (c)  Number of shares as to which the person has:

          (i)   Sole power to vote or to direct the vote 
                (See Page 2, No. 5)
                --------------------
                         
          (ii)  Shared power to vote or to direct the vote 
                (See Page 2, No. 6)
                --------------------
                         
          (iii) Sole power to dispose or to direct the disposition of  
                (See Page 2, No. 7)
                --------------------

          (iv)  Shared power to dispose or to direct the disposition of  
                (See Page 2, No. 8)
                --------------------

Item 5.  Ownership of Five Percent or Less of a Class.

              If this statement is being filed to report the fact that as of the
         date hereof the reporting person has ceased to be the beneficial owner
         of more than five percent of the class of securities, check the
         following: [_]

Item 6.  Ownership of More than Five Percent on Behalf of Another Person.

              All securities reported upon this Schedule are owned by investment
         advisory clients of Ariel Capital Management, Inc. no one of which to
         the knowledge of Ariel Capital Management, Inc. owns more than 5% of 
         the class.

Item 7.  Identification and Classification of the Subsidiary Which Acquired the
         Security Being Reported on by the Parent Holding Company.

         Not applicable
         --------------

Item 8.  Identification and Classification of Members of the Group.

         Not applicable
         --------------

<PAGE>

                                                          Date:      4/30/99
                                                                 ---------------
                                                                   Page 5 of 5
 


                                   SIGNATURE

     The undersigned hereby agree that this statement is being filed on behalf 
of each of them and hereby certify, after reasonable inquiry and to the best of 
their knowledge and belief, that the information set forth in this statement is 
true, complete and correct.

                                       ARIEL CAPITAL MANAGEMENT, INC.


                                       By:  /s/ Eric T. McKissack
                                           ------------------------------
                                               Eric T. McKissack
                                               Co-Chief Investment Officer and 
                                               Senior Vice President



                                       JOHN W. ROGERS, JR.*
                                       --------------------
                                       JOHN W. ROGERS, JR.


                                       *By:  /s/ Eric T. McKissack
                                            ------------------------------
                                               Eric T. McKissack



DATED: May 10, 1999
      -------------

     * Eric T. McKissack signs this document on behalf of John W. Rogers, Jr.
pursuant to the power of attorney attached as Exhibit 1 to the Schedule 13G
filed with the Securities and Exchange Commission on or about January 10, 1994,
on behalf of Ariel Capital Management, Inc. and John W. Rogers, Jr. with respect
to Oshkosh B'Gosh, Incorporated, which said power of attorney is hereby
incorporated by reference.