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                                                                EXHIBIT 10.20(b)

                            SECOND AMENDMENT TO THE
            AMENDED AND RESTATED LIMITED LIABILITY COMPANY AGREEMENT
                                      FOR

                  CHARTER COMMUNICATIONS HOLDING COMPANY, LLC
                      A DELAWARE LIMITED LIABILITY COMPANY

     This Second Amendment to the Amended and Restated Limited Liability Company
Agreement for Charter Communications Holding Company, LLC, a Delaware limited
liability company ("COMPANY"), is adopted effective as of October 24, 2000
("EFFECTIVE DATE") by Charter Communications, Inc., a Delaware corporation
("PUBLICCO"), with reference to the following facts:

     A. The Company is being operated pursuant to that certain Amended and
Restated Limited Liability Company Agreement entered into and made effective as
of February 14, 2000, by and among Charter Investment, Inc, Vulcan Cable III
Inc., PublicCo, and certain other parties, as amended (the "LLC AGREEMENT").
Unless otherwise defined, capitalized terms used herein have the meanings
assigned to them in the LLC Agreement.

     B. In connection with certain transactions entered into or to be entered
into by PublicCo and its subsidiaries, the certificate of incorporation of
PublicCo has been amended. PublicCo desires to make certain conforming changes
to the LLC Agreement.

     C. Section 10.11 of the LLC Agreement provides that an amendment to the LLC
Agreement to incorporate the changes made by this Second Amendment shall be
effective as an amendment upon the approval of Members holding more than fifty
percent (50%) of the Class B Common Units. On the Effective Date, PublicCo owns
all outstanding Class B Common Units and desires to approve the amendments to
the LLC Agreement made by this Second Amendment.

     NOW, THEREFORE, the LLC Agreement is hereby amended as follows:

          1. Section 2.5 of the LLC Agreement is amended and restated in its
     entirety to read as follows:

             2.5 Purpose of Company.  The Company may carry on any lawful
        business, purpose, or activity that may be carried on by a limited
        liability company under applicable law; (i) provided, however, that,
        until all outstanding shares of Class B Common Stock have been converted
        into shares of Class A Common Stock in accordance with Clause (b)(viii)
        of Article Fourth of PublicCo's certificate of incorporation as
        constituted as of the Class B Common Measuring Date, without the
        Approval of the Class A Common Members, the Company shall not engage
        directly or indirectly, including without limitation through any
        Subsidiary, in any business other than (A) the Cable Transmission
        Business (as defined below), (B) as a member or shareholder of, and
        subscriber to, the portal joint venture with Broadband Partners, (C) as
        an owner and operator of the business of Interactive Broadcaster
        Services Corporation, a California corporation, which shall include
        solely the ownership of its assets and continuation of its business
        substantially as owned and conducted as of September 13, 2000, (D) as a
        member of and service provider to the joint venture for the development
        of a licensable reference design for a cable set-top box with
        functionalities of a video cassette recorder and a personal video
        recorder, (E) as a member of Cable Sports Southeast, LLC, a Delaware
        limited liability company ("Cable Sports"), so long as Cable Sports
        continues to conduct substantially the same business conducted by it on
        October 24, 2000, and (F) as a shareholder of High Speed Access Corp., a
        Delaware corporation ("HSA"), so long as HSA continues to conduct
        substantially the same business as conducted by it at the time of the
        consummation of the transactions contemplated by the Stock Purchase
        Agreement dated as of October 19, 2000 among Charter Communications
        Ventures, LLC, HSA and Vulcan Ventures Incorporated, as it may be
        amended from time to time; (ii) provided further, that to the extent
        that, as of the Class B Common Measuring Date, the Company was directly
        or indirectly engaged in or had agreed to acquire directly
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        or indirectly any business other than the Cable Transmission Business or
        as a member of, and subscriber to, the portal joint venture with
        Broadband Partners (any such other business, an "INCIDENTAL BUSINESS,"
        and collectively, "INCIDENTAL BUSINESSES"), so long as (a) such
        Incidental Businesses so engaged in by the Company on the Class B Common
        Measuring Date in the aggregate on such date accounted for less than ten
        percent (10%) of the consolidated revenues of the total business engaged
        in by the Company or (b) such Incidental Businesses which on the Class B
        Common Measuring Date the Company had agreed to acquire in the aggregate
        on such date accounted for less than ten percent (10%) of the
        consolidated revenues of the total businesses to be acquired, as
        applicable, the Company may, directly or indirectly, including through
        any Subsidiary, continue to conduct any such Incidental Business and the
        foregoing limitation on the business and purpose of the Company shall
        not require that any such Incidental Business be divested by the
        Company, but the Company shall not, directly or indirectly, expand any
        such Incidental Business by means of any acquisition or any commitment
        of the Company or its Subsidiaries' resources or financial support.
        "CABLE TRANSMISSION BUSINESS" means the transmission of video, audio
        (including telephony) and data over cable television systems owned,
        operated or managed by the Company or its Subsidiaries; provided, that
        the businesses of RCN Corporation and its Subsidiaries shall not be
        deemed to be a Cable Transmission Business.

          2. The first two paragraphs of Section 5.7 are amended and restated in
     their entirety to read as follows:

             5.7 Competing Activities.  Except as provided by any individual
        contract: (i) any Manager or Member (and their respective officers,
        directors, agents, shareholders, members, partners or Affiliates) may
        engage or invest in, independently or with others, any business activity
        of any type or description, including without limitation those that
        might be the same as or similar to the Company's business or the
        business of any Subsidiary and that might be in direct or indirect
        competition with the Company or any Subsidiary; (ii) neither the Company
        or any Subsidiary nor any Member shall have any right in or to such
        other ventures or activities or to the income or proceeds derived
        therefrom; (iii) no Manager or Member (and their respective officers,
        directors, agents, shareholders, members, partners or Affiliates) shall
        be obligated to present any investment opportunity or prospective
        economic advantage to the Company or any Subsidiary, even if the
        opportunity is of the character that, if presented to the Company or any
        Subsidiary, could be taken by the Company or any Subsidiary; and (iv)
        any Manager or Member (and their respective officers, directors, agents,
        shareholders, members, partners or Affiliates) shall have the right to
        hold any investment opportunity or prospective economic advantage for
        such Manager's or Member's (and their respective officers', directors',
        agents', shareholders', members', partners' or Affiliates') own account
        or to recommend such opportunity to Persons other than the Company or
        any Subsidiary; (i) provided that as a condition to election as Manager
        and receiving a Membership Interest in the Company upon consummation of
        the IPO, PublicCo agrees that until all outstanding shares of Class B
        Common Stock have been converted into shares of Class A Common Stock in
        accordance with Clause (b)(viii) of Article Fourth of PublicCo's
        certificate of incorporation as constituted as of the Class B Common
        Measuring Date, it shall not engage directly or indirectly, including
        without limitation through any Subsidiary, in any business other than
        (A) the Cable Transmission Business, (B) as a member or shareholder of,
        and subscriber to, the portal joint venture with Broadband Partners; (C)
        as an owner and operator of the business of Interactive Broadcaster
        Services Corporation, a California corporation, which shall include
        solely the ownership of its assets and continuation of its business
        substantially as owned and conducted as of September 13, 2000; (D) as a
        member of and service provider to the joint venture for the development
        of a licensable reference design for a cable set-top box with
        functionalities of a video cassette recorder and a personal video
        recorder; (E) as a member of Cable Sports Southeast, LLC, a Delaware
        limited liability company ("Cable Sports"), so long as Cable Sports
        continues to conduct substantially the same business conducted by it on
        October 24, 2000; and (F) as a shareholder of High Speed Access Corp., a
        Delaware corporation ("HSA"), so long as HSA continues to conduct
        substantially the same business as conducted by it at the time of the
        consummation of the transactions contemplated by the
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        Stock Purchase Agreement dated as of October 19, 2000 among Charter
        Communications Ventures, LLC, HSA and Vulcan Ventures Incorporated, as
        it may be amended from time to time; (ii) provided further, that to the
        extent that, as of the Class B Common Measuring Date, PublicCo was
        directly or indirectly engaged in, or had agreed to acquire directly or
        indirectly, an Incidental Business, so long as (a) such Incidental
        Businesses so engaged in by PublicCo on the Class B Common Measuring
        Date in the aggregate on such date accounted for less than ten percent
        (10%) of the consolidated revenues of the total business engaged in by
        PublicCo, or (b) such Incidental Businesses which on the Class B Common
        Measuring Date PublicCo had agreed to acquire in the aggregate on such
        date accounted for less than ten percent (10%) of the consolidated
        revenues of the total businesses to be acquired, as applicable, PublicCo
        may, directly or indirectly, including through any Subsidiary, continue
        to conduct any such Incidental Business and the foregoing limitation on
        the business and purpose of PublicCo shall not require that any such
        Incidental Business be divested by PublicCo, but PublicCo shall not,
        directly or indirectly, expand any such Incidental Business by means of
        any acquisition or any commitment of PublicCo or its Subsidiaries'
        resources or financial support. PublicCo also agrees that it shall not
        (i) hold any assets, other than (a) working capital cash and cash
        equivalents held for the payment of current obligations and receivables
        from the Company; (b) Common Units; (c) back-to-back obligations and
        mirror equity interests of the Company, consisting of obligations and
        equity securities (other than Common Units, but including convertible
        securities), which are substantially equivalent to liabilities or
        obligations or securities of PublicCo to third parties; (d) assets
        subject to an existing obligation to contribute such assets (or
        successor assets) to the Company in exchange for Units; (e) assets
        acquired as a result of the issuance of (x) common stock of PublicCo
        and/or preferred stock of PublicCo and/or (y) liabilities or obligations
        of PublicCo, subject to an existing obligation to contribute such assets
        (or successor assets) to the Company in exchange for Common Units (in
        respect of the common stock of PublicCo issued) and/or for mirror equity
        securities (other than Common Units, but including convertible
        securities, in respect of the mirror equity securities issued) of the
        Company and/or liabilities or obligations of the Company (in respect of
        the liabilities or obligations incurred), which are substantially
        equivalent to the equity securities and/or liabilities and obligations
        of PublicCo issued to acquire such assets; or (f) goodwill or deferred
        tax assets, or (ii) incur any liabilities or obligations for borrowed
        money, for acquisition of assets or under any capital lease, other than
        (a) in connection with back-to-back obligations of the Company to
        PublicCo consisting of liabilities or obligations of the Company which
        are substantially equivalent to liabilities or obligations of PublicCo
        to a third party; (b) liabilities or obligations incident to the
        acquisition of Units in exchange for common stock of PublicCo; or (c)
        liabilities or obligations as contemplated by Clauses (i)(d) and (e)
        immediately above. PublicCo further agrees (x) that it shall not issue,
        transfer from treasury stock or repurchase shares of its common stock
        unless in connection with any such issuance, transfer, or repurchase
        PublicCo takes all requisite action such that, after giving effect to
        all such issuances, transfers or repurchases, the number of outstanding
        shares of common stock will equal on a one-for-one basis the number of
        Common Units owned by PublicCo; (y) that it shall not issue, transfer
        from treasury stock or repurchase shares of preferred stock of PublicCo
        unless in connection with any such issuance, transfer or repurchase
        PublicCo takes all requisite action such that, after giving effect to
        all such issuances, transfers or repurchases, PublicCo holds mirror
        equity interests of the Company which are in the aggregate substantially
        equivalent to the outstanding preferred stock of PublicCo; and (z) upon
        any reclassification of the Common Units, whether by combination,
        division or otherwise, it shall take all requisite action so that the
        number of outstanding shares of common stock will equal on a one-for-one
        basis the number of Common Units owned by PublicCo.

             The Company agrees that, until all outstanding shares of Class B
        Common Stock have been converted into shares of Class A Common Stock in
        accordance with Clause (b)(viii) of Article Fourth of PublicCo's
        certificate of incorporation as constituted as of the Class B Common
        Measuring Date, without the Approval of the Class A Common Members, (i)
        the Company shall not engage directly or indirectly, including without
        limitation through any Subsidiary, in any
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        business other than (A) the Cable Transmission Business, (B) as a member
        or shareholder of and subscriber to, the portal joint venture with
        Broadband Partners, (C) as an owner and operator of the business of
        Interactive Broadcaster Services Corporation, a California corporation,
        which shall include solely the ownership of its assets and continuation
        of its business substantially as owned and conducted as of September 13,
        2000, (D) as a member of and service provider to the joint venture for
        the development of a licensable reference design for a cable set-top box
        with functionalities of a video cassette recorder and a personal video
        recorder, (E) as a member of Cable Sports Southeast, LLC, a Delaware
        limited liability company ("Cable Sports"), so long as Cable Sports
        continues to conduct substantially the same business conducted by it on
        October 24, 2000, and (F) as a shareholder of High Speed Access Corp., a
        Delaware corporation ("HSA"), so long as HSA continues to conduct
        substantially the same business as conducted by it at the time of the
        consummation of the transactions contemplated by the Stock Purchase
        Agreement dated as of October 19, 2000 among the Charter Communications
        Ventures, LLC, HSA and Vulcan Ventures Incorporated, as it may be
        amended from time to time; and (ii) to the extent that, as of the Class
        B Common Measuring Date, the Company was directly or indirectly engaged
        in, or had agreed to acquire directly or indirectly, an Incidental
        Business, so long as (a) such Incidental Businesses so engaged in by the
        Company on the Class B Common Measuring Date in the aggregate on such
        date accounted for less than ten percent (10%) of the consolidated
        revenues of the total business engaged in by the Company or (b) such
        Incidental Businesses which on the Class B Common Measuring Date the
        Company had agreed to acquire in the aggregate on such date accounted
        for less than ten percent (10%) of the consolidated revenues of the
        total businesses to be acquired, as applicable, the Company may,
        directly or indirectly, including through any Subsidiary, continue to
        conduct any such Incidental Business and the foregoing limitation on the
        business and purpose of the Company shall not require that any such
        Incidental Business be divested by the Company, but the Company shall
        not, directly or indirectly, expand any such Incidental Business by
        means of any acquisition or any commitment of the Company or its
        Subsidiaries' resources or financial support.

     IN WITNESS WHEREOF, the undersigned has executed this Second Amendment,
effective as of the date first written above.

                                          Charter Communications, Inc.

                                          By: /s/    CURTIS S. SHAW
                                            ------------------------------------
                                            Curtis S. Shaw
                                            Senior Vice President