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                                                                    Exhibit 4a
                                                                    ----------


                         AMENDMENT TO RIGHTS AGREEMENT

AMENDMENT,  dated as of April  1, 1996, to  the Rights Agreement,  dated as of
September  22, 1989 (the "Rights Agreement"), between Pacific Telesis Group, a
Nevada corporation (the  "Company"), and The First National Bank of Boston, as
Rights Agent (the "Rights Agent").

WHEREAS, the Company and the Rights Agent have heretofore
executed and entered into the Rights Agreement; and

WHEREAS, pursuant to Section 27 of  the Rights Agreement, the Company may from
time to time prior to the Distribution Date (as defined therein) supplement or
amend  the Rights Agreement  in accordance with  the provisions  of Section 27
thereof; and

WHEREAS, it is proposed that the  Company enter into an Agreement and Plan  of
Merger (as it may  be amended or supplemented  from time to time,  the "Merger
Agreement"),  among  the Company,  SBC  Communications  Inc. ("SBC")  and  SBC
Communications (NV) Inc., a Nevada corporation ("Merger Sub"); and

WHEREAS, the  Board of Directors of the Company has determined that the Merger
and the other transactions  contemplated by the Merger  Agreement are fair  to
and in the best interests,of the Company and its stockholders; and

WHEREAS, the Board of Directors has determined that it is in the best interest
of the  Company and its stockholders  to amend the Rights  Agreement to exempt
the  Merger  Agreement and  the  transactions  contemplated thereby  from  the
application of the Rights Agreement.

NOW, THEREFORE, the Company and the Rights Agent hereby
amend the Rights Agreement as follows:

     1.   Section l(a) of the Rights Agreement is hereby amended by adding the
          following sentence at the end thereof:

          "Neither SBC Communications,  Inc., a Delaware  corporation ("SBC"),
          SBC   Communications  (NV)   Inc.,  a   Nevada  corporation   and  a
          wholly-owned  subsidiary of Parent ("Merger Sub"),  nor any of their
          respective Subsidiaries, shall  be deemed to be an  Acquiring Person
          with respect to-and  to the extent that  shares of Common Stock  are
          acquired by  such entities  or their  Affiliates or  Subsidiaries in
          connection with  the transactions contemplated by  the Agreement and
          Plan of  Merger (as it may  be amended or supplemented  from time to
          time,  the "Merger  Agreement") entered  into as  of April  1, 1996,
          among the Company, SBC and Merger Sub."

     2.   Section l(b) of the Rights Agreement is hereby amended by adding the
          following sentence at the end thereof:

          "Neither  SBC,   nor  Merger  Sub   nor  any  of   their  respective
          Subsidiaries, shall be deemed  to be an Adverse Person  with respect
          to and to  the extent that  shares of Common  Stock are acquired  by

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                                    <PAGE>

          such entities or their Affiliates or Subsidiaries in connection with
          the transactions contemplated by the Merger Agreement."

     3    Section 30  of the  Rights Agreement  is hereby  amended to add  the
          following sentence at the end thereof:

          "Nothing in  this Agreement shall be construed  to create or cause a
          Distribution  Date or Stock Acquisition  Date or give  any holder of
          Rights or any  other Person any legal or equitable rights, remedy or
          claim under this Agreement in  connection with the Merger  Agreement
          or any transactions contemplated by the Merger Agreement."

     4.   Sections 24(a)(i),  (a)(ii) and (b)  are hereby amended  by deleting
          each  subsection  in  its  entirety and  substituting  therefor  the
          following:

          "24.  Termination and Exchange.

          (a)(i) The  Board of Directors of the Company may, at its option, at
          any  time prior to the earlier of  (x) the Stock Acquisition Date or
          such time as any Person may become an  Adverse Person or (y) 5 p.m.,
          San  Francisco time,  on the  Final Expiration  Date, terminate  the
          Rights without any payment to any holder thereof.

          (ii) In  addition, and  notwithstanding  the  provisions of  Section
          24(a)(i),  the Board of Directors  of the Company  may terminate the
          Rights without any payment to any holder thereof following the Stock
          Acquisition  Date or such  time as any Person  may become an Adverse
          Person but prior to any event described in Section 13(a)  either (x)
          in connection with any event specified in Section 13(a) in which all
          holders of Common Stock  are treated alike and not  involving (other
          than  as a holder of Common Stock  being treated like all other such
          holders)  an Acquiring Person or  adverse Person or  an Affiliate of
          Associate  thereof  or any  other  Person  in  which such  Acquiring
          Person, Adverse  Person or  Affiliate or  Associate thereof has  any
          interest,  or any  other  Person acting  directly  or indirectly  on
          behalf  of or in association with any such Acquiring Person, Adverse
          Person, or  Affiliate or  Associate  thereof, or  (y) following  the
          occurrence of  an  event set  forth in,  and the  expiration of  any
          periods  during which the holder  of Rights may  exercise the rights
          under section 11(a)(ii) if  and for as long as  any.Acquiring Person
          having  triggered such event is not  thereafter the Beneficial Owner
          of  securities representing 20% or more of the outstanding shares of
          the Voting Power, and at the time of termination there  are no other
          Persons who are Acquiring Persons or Adverse Persons.

          (b)  In the case of a termination permitted under Section  24(a)(i),
          immediately upon the action of the Board of Directors of the Company
          ordering the termination of the Rights, evidence of which shall have
          been filed with the Rights Agent and without  any further action and
          without  any notice, the right to exercise the Rights will terminate
          and each right will thereafter be null  and void.  In the case of  a
          termination  permitted only  under  Section  24(a)(ii), evidence  of
          which shall  have been  filed with  the Rights  Agent, the  right to
          exercise the Rights will terminate and each right will thereafter be
          null and  void only after  10 Business Days following  the giving of

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                                    <PAGE>

          notice of such termination to the holders of such Rights if no event
          set forth in  Section 11(a)(ii)  shall have occurred,  and, if  such
          event  shall have  occurred,  upon the  later  of 10  Business  Days
          following the giving of  such notice or the expiration of any period
          during which the  rights under Section  11(a)(ii) may be  exercised.
          Within 10 days after the  action of the Board of Directors  ordering
          any termination of the Rights, the Company shall give notice of such
          termination  to the  Rights  Agent  and  the  holders  of  the  then
          outstanding Rights by mailing such notice to the Rights Agent and to
          all such  holders at their  last addresses  as they appear  upon the
          registry books of  the Rights  Agent or, prior  to the  Distribution
          Date, on  the registry books  of the Transfer  Agent for  the Common
          Stock.   Any notice  which is mailed  in the manner  herein provided
          shall  be deemed  given,  whether or  not  the holder  receives  the
          notice.

     5.   Section 24 of the Rights Agreement is hereby amended by adding a new
          subsection (d) thereto:

          "(d) Notwithstanding  anything in  this Agreement, the  Rights shall
          terminate  without any  payment  to any  holder thereof  immediately
          prior to the Effective Time as defined in the Merger Agreement."

     6.   The  second paragraph  of Section  3(a) of  the Rights  Agreement is
          hereby amended by deleting the word "redemption" and the immediately
          following   comma  in   the  parentheticals  following   the  phrase
          "Distribution Date" in each of the ninth and fifteenth lines of such
          second paragraph.

     7.   Section 3(b) of the  Rights Agreement is hereby amended  as follows:
          (a)  the  legend  forming  a  part of  Section  3(b)  to  the Rights
          Agreement is hereby amended  by deleting the word "redeemed"  in the
          eleventh line of such legend immediately following the  phrase "such
          Rights  may be" and substituting therefor the word "terminated," and
          (b) in the parenthetical in the last paragraph of Section 3(b),  the
          word "redemption" shall be deleted.

     8.   Clause  (ii) of  Section  7(a) of  the  Rights Agreement  is  hereby
          amended  by deleting in its entirety Clause (ii) and substituting in
          its place the following:

          "(ii) the  time at  which the Rights  are terminated as  provided in
          Section 24 hereof,"

     9.   Section  23 of the Rights Agreement  is hereby amended to delete the
          word   "redemption"  in   line  twelve   and  substitute   the  word
          "termination" therefor.

     10.  Section 28 of the Rights Agreement is hereby amended by deleting the
          word "redeem" in each place in the parenthetical  in clause (ii) and
          substituting the word "terminate" therefor.

     11.  This Amendment shall be deemed to be a contract made  under the laws
          of the State of Nevada and for all purposes shall be governed by and
          construed  in accordance with the  laws of such  state applicable to
          contracts to be made and performed entirely within such state.

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                                    <PAGE>

     12.  This Amendment may be  executed in any number of  counterparts, each
          of which  shall for all purposes  be deemed an original,  and all of
          which together shall constitute but one and the same instrument.


Except as expressly set forth herein, this Amendment  shall not by implication
or otherwise  alter, modify,  amend or  in any  way affect any  of the  terms,
conditions,  obligations,  covenants or  agreements  contained  in the  Rights
Agreement, all  of which are ratified  and affirmed in all  respects and shall
continue in full force and effect.

IN WITNESS WHEREOF,  the parties hereto have caused this  Amendment to be duly
executed and the respective corporate seals to be affixed and attested, all as
of the day and year first above written.



Attest:                            PACIFIC TELESIS GROUP

    [SEAL]


/s/ Duane G. Henry                 /s/ Jim R. Moberg
Duane G. Henry                     Jim R. Moberg
Assistant Secretary                Executive Vice President



Attest:                            THE FIRST NATIONAL BANK OF
                                   BOSTON
   [SEAL]


/s/ Deborah N. Norris              /s/ Darlene M. DioDato
Deborah N. Norris                  Darlene M. DioDato
Director                           Managing Director





















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