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                                                                   EXHIBIT 10.37


                          REGISTRATION RIGHTS AGREEMENT


     THIS REGISTRATION RIGHTS AGREEMENT (this "Agreement") dated as of April 8,
1999, by and between United International Holdings, Inc., a Delaware corporation
(the "Company"), and Riordan Communications Limited  (the "Stockholder," and
together with any permitted transferees party hereto pursuant to Section 12
hereof, the "Stockholders").

                                    Recitals
                                    --------

     A.   This Agreement is made with respect to the 384,531 shares of  Common
Stock (as defined below) held on the date hereof by the Stockholder (the
"Shares").

     B.   The Company and the Stockholder desire to enter into this Agreement
pursuant to which, among other things, the Stockholder has the right to cause
the Company, upon request, to register with the Commission (as defined below) an
offering and sale of shares of Common Stock held by the Stockholder, subject to
the terms of this Agreement.

                                   Agreement
                                   ---------

     1.   Definitions.  As used in this Agreement, the following capitalized
          -----------
terms shall have the following respective meanings:

          (a) Affiliate.  Any Person that, directly or indirectly, through one
              ---------
or more intermediaries, controls, or is controlled by, or is under common
control with, the Stockholder.

          (b) Commission.  The United States Securities and Exchange Commission
              ----------
or any other Federal agency at the time administering the Securities Act.

          (c) Common Stock.  The Class A Common Stock, $.01 par value per share,
              ------------
of the Company.

          (d) Exchange Act.  The Securities Exchange Act of 1934, as amended, or
              ------------
any successor Federal statute, and the rules and regulations of the Commission
thereunder.

          (e) Person.  Any individual, corporation, partnership, trust,
              ------
organization, association, governmental body or agency.

          (f) Registrable Securities.  The (i) Shares and (ii) any shares of
              ----------------------
Common Stock which may be issued or distributed in respect thereof by way of
stock dividend or stock split or other distribution, recapitalization, merger,
consolidation or reclassification or other reorganization or otherwise.  A
Registrable Security shall cease to be a Registrable Security when:  (A) a
registration
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statement with respect to the sale of such security shall have become effective
under the Securities Act and such security shall have been disposed of in
accordance with such registration statement; (B) such security shall have been
otherwise transferred and new certificates for such security not bearing a
legend restricting further transfer shall have been delivered by the Company; or
(C) such security shall have ceased to be outstanding.

          (g) Registration Expenses.  As set forth in Section 8 hereof.
              ---------------------

          (h) Securities Act.  The Securities Act of 1933, as amended, or any
              --------------
successor Federal statute, and the rules and regulations of the Commission
thereunder.

     2.   Demand Registration.
          -------------------

          (a) Upon the written request of Stockholders holding an aggregate of
50% of the outstanding Registrable Securities requesting that the Company effect
the registration under the Securities Act of all or part of the Registrable
Securities owned by such Stockholders and specifying the intended method of
disposition thereof, but subject to the limitations set forth herein, the
Company will promptly (but in no event more than five business days after the
receipt of such request) give written notice of such requested registration to
all other Stockholders, and the Company shall file with the Commission as
promptly as practicable after sending such notice, and use its best efforts to
cause to become effective, a registration statement under the Securities Act
registering the offering and sale of:

               (i)  the Registrable Securities which the Company has been so
     requested to register by the Stockholders, and

               (ii) all other Registrable Securities which the Company has been
     requested to register by any other Stockholder by written request given to
     the Company within 30 days after the giving of such written notice by the
     Company (which request shall specify the intended method of disposition of
     such Registrable Securities),

all to the extent necessary to permit the disposition (in accordance with the
intended method thereof as aforesaid) of the Registrable Securities so to be
registered (a "Demand Registration"); provided, that (A) the Company shall not
be obligated to file a registration statement pursuant to this Section 2(a) with
respect to more than an aggregate of two registrations, and (B) the Company
shall not be obligated to file a registration statement pursuant to this Section
2(a) unless the aggregate amount of Registrable Securities that any Stockholders
seek to register pursuant to such Section constitutes at least 50% of all
Registrable Securities held by Stockholders.

          (b) If in accordance with Section 10 hereof a requested registration
pursuant to this Section 2 is to be in the form of an underwritten offering
through underwriters, the Company shall designate as underwriters investment
banking firms of national reputation that are satisfactory

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to the Stockholders holding a majority of the Registrable Securities to be
included in such registration. If a requested registration pursuant to this
Section 2 involves an underwritten offering and the managing underwriter advises
the Company in writing that, in its opinion, the number of securities requested
to be included in such registration (including securities of the Company which
are not Registrable Securities) exceeds the number which can be sold in such
offering without a significant adverse effect on the price, timing or
distribution of the Registrable Securities offered, the Company will (subject to
the last sentence of this paragraph) include in such registration only the
Registrable Securities requested to be included in such registration. In the
event that the number of Registrable Securities requested to be included in such
registration exceeds the number which, in the opinion of such managing
underwriter, can be sold, then the Company will include in such registration
only the number of Registrable Securities which, in the opinion of the managing
underwriter, can be sold, such number to be allocated pro rata among all
requesting Stockholders on the basis of the relative number of shares of
Registrable Securities then held by each such holder (provided, that any shares
thereby allocated to any such holder that exceed such holder's request shall be
reallocated among the remaining requesting holders of Registrable Securities in
like manner). In the event that the number of Registrable Securities requested
to be included in such registration is less than the number which, in the
opinion of the managing underwriter, can be sold, the Company may include in
such registration the securities the Company or any other holder of the
Company's securities proposes to sell up to the number of securities that, in
the opinion of the managing underwriter, can be sold without an adverse effect
on the price, timing or distribution of the Registrable Securities offered.

          (c) The Company shall be entitled to postpone for a reasonable period
of time (not to exceed 120 days, which may not thereafter be extended) the
filing of any registration statement otherwise required to be prepared and filed
by it pursuant to Section 2(a) hereof if, at the time it receives a request for
such registration, the Board of Directors of the Company determines in good
faith that such offering will materially interfere with a pending or
contemplated financing, merger, sale of assets, recapitalization or other
similar corporate action of the Company, in which case the Company shall have
furnished to holders of Registrable Securities requesting such registration an
officers' certificate to that effect.  After such period of postponement the
Company shall effect such registration as promptly as practicable without
further request from the holders of Registrable Securities, unless such request
has been withdrawn.

     3.   Piggy-back Registration.
          -----------------------

          (a) If the Company shall at any time propose to file a registration
statement under the Securities Act for an offering of securities of the Company
for resale by holders of the Company's securities other than Registrable
Securities (the "Requesting Holders"), the Company shall provide prompt written
notice of such proposal, in any event, not less than 15 days before the
anticipated filing date, to all Stockholders of its intention to do so and of
such Stockholders' rights under this Section 3. The Company shall use its best
efforts to include such number of Registrable Securities in such registration
statement which the Company has been so requested to register by any Requesting
Holder (a "Piggy-back Registration"), which request shall be made to the Company

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within 15 days after such Stockholders receive notice from the Company of such
proposed registration; provided, that (i) if, at any time after giving written
notice of its intention to register any securities and prior to the effective
date of the registration statement filed in connection with such registration,
the Company shall determine for any reason not to register such securities, the
Company may, at its election, give written notice of such determination to each
Stockholder and, thereupon, shall be relieved of its obligation to register any
Registrable Securities in connection with such registration, and (ii) if such
registration involves an underwritten offering, all holders of Registrable
Securities requesting to be included in the registration must sell their
Registrable Securities to the underwriters on the same terms and conditions as
apply to the Requesting Holders, with such differences, including any with
respect to indemnification and liability insurance, as may be customary or
appropriate in secondary offerings.  Any Stockholder requesting pursuant to this
Section 3 to be included in a registration may elect, in writing prior to the
effective date of the registration statement filed in connection with such
registration, not to register such securities in connection with such
registration.

          (b) If a registration pursuant to this Section 3 involves an
underwritten offering as to which any Stockholder has requested a Piggy-back
Registration and the managing underwriter reasonably and in good faith advises
the Company in writing that, in its opinion, the number of securities to be
included in such registration exceeds the number which can be sold in such
offering without an adverse effect on the price, timing or distribution of such
offering, then (i) first, the number of securities which the Company's security
holders other than the Requesting Holders requested to be included in such
registration shall be reduced as necessary pro rata in proportion to the
relative number of securities requested by each such holder to be included until
the number of securities to be included in such registration no longer exceeds
the number which can be sold in such offering, and (ii) second, the number of
securities which the Requesting Holders requested to be included in such
registration shall be reduced as applicable until the number of securities to be
included in such registration no longer exceeds the number which can be sold in
such offering.

     4.   Suspension of Registration Obligation.  The Company shall not be
          -------------------------------------
required to register the sale of its securities under this Agreement for any
Stockholder if there is available for such transaction an appropriate exemption
from registration under the Securities Act.

     5.   Limitation on Registration Rights.  Each Stockholder acknowledges that
          ---------------------------------
the Company and certain stockholders ("Other Stockholders") are parties to
certain Registration Rights Agreements (the "Existing Agreements"), pursuant to
which the Company has granted registration rights to the Other Stockholders.
Each Stockholder hereby agrees that, notwithstanding any other provision of this
Agreement, the Stockholders shall not have any rights under this Agreement that
are inconsistent with the rights granted to the Other Stockholders under the
Existing Agreements, unless otherwise consented to by the Other Stockholders.

     6.   Hold-Back Agreements.  Each Stockholder agrees in connection with any
          --------------------
registration effected by the Company (other than an offering relating to (i) a
business combination that is to be filed on Form S-4 under the Securities Act
(or any successor form thereto) or (ii) an employee

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benefit plan) of the Company's securities not to effect any public sale or
distribution of securities of the Company the same as or similar to those being
registered, or any securities convertible into or exchangeable or exercisable
for such securities, including a sale pursuant to Rule 144 under the Securities
Act, except as part of such registration, during the 14-day period prior to, and
during the 90-day period (or, with respect to a Piggy-back Registration, such
longer period of up to 120 days as may be requested by such managing
underwriter) beginning on, the effective date of the related registration
statement, to the same extent requested by the managing underwriters and
applicable to other holders of the Company's securities subject to similar
agreements. Each Stockholder agrees to execute an undertaking in accordance with
the foregoing in the form reasonably requested by the managing underwriters.

     7.   Registration.
          ------------

          (a) Whenever any Registrable Securities are to be registered pursuant
to Section 2 or 3 of this Agreement, the Company will use its best efforts to
effect the registration and the sale of such Registrable Securities under the
Securities Act in accordance with the intended method of disposition thereof.

          (b) The Company may require each Stockholder requesting a registration
pursuant to Section 2 or 3 to furnish to the Company such information regarding
the distribution of such securities and such other information relating to such
Stockholder and its ownership of Registrable Securities as the Company may from
time to time reasonably request in writing.   Each such Stockholder agrees to
furnish such information to the Company and to cooperate with the Company as
necessary to enable the Company to comply with the provisions of this Agreement.

          (c) Upon receipt of any notice from the Company at any time when a
prospectus relating to the registration is required to be delivered under the
Securities Act of the occurrence of any event as a result of which the
prospectus included in such registration statement (as then in effect) contains
an untrue statement of a material fact or omits to state a material fact
necessary to make the statements therein, in light of the circumstances under
which they were made, not misleading, the Stockholders selling Registrable
Securities will forthwith discontinue disposition of the Registrable Securities
until receipt of copies of a supplemented or amended prospectus or until such
Stockholders are advised in writing (the "Advice") by the Company that the use
of the prospectus may be resumed, and have received copies of any additional or
supplemental filings which are incorporated by reference in the prospectus and,
if so directed by the Company, such Stockholders will, or will request the
managing underwriter or underwriters, if any, to, deliver to the Company (at the
Company's expense) all copies, other than permanent file copies then in such
holder's possession of the prospectus covering such Registrable Securities
current at the time of receipt of such notice.

     8.   Registration Expenses.  Except as otherwise agreed in accordance with
          ---------------------
Section 2(a), all expenses incident to the Company's performance of or
compliance with this Agreement including, without limitation, all Commission and
securities exchange or National Association of

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Securities Dealers registration and filing fees, fees and expenses of compliance
with securities or blue sky laws (including reasonable fees and disbursements of
counsel in connection with blue sky qualifications of the Registrable
Securities), rating agency fees, printing expenses, messenger and delivery
expenses, internal expenses (including, without limitation, all salaries and
expenses of the Company's officers and employees performing legal or accounting
duties), the fees and expenses incurred in connection with the listing of the
securities to be registered, if any, on each securities exchange on which
similar securities issued by the Company are then listed and reasonable fees and
disbursement of counsel for the Company and its independent certified public
accountants (including the expenses of any special audit or "cold comfort"
letters required by or incident to such performance), Securities Act liability
insurance (if the Company elects to obtain such insurance) and the reasonable
fees and expenses of any special experts retained by the Company in connection
with such registration (all such expenses being herein called "Registration
Expenses") will be borne by the Company; provided, that Registration Expenses
shall not include, and the Company shall not be responsible for any underwriting
fees, discounts or commissions attributable to the sale of Registrable
Securities or any other expenses incurred by the Stockholders in connection with
such registration, which shall be paid by the Stockholders requesting such
registration.

     9.   Term.  The registration rights set forth in Sections 2 and 3 hereof
          ----
shall not be available to any Stockholder if, in the opinion of counsel to the
Company, all of the Registrable Securities then owned by such Stockholder could
be sold in any 90-day period pursuant to Rule 144.

     10.  Underwritten Offerings.
          ----------------------

          (a) Stockholders may request that any registration pursuant to Section
2 of Registrable Securities be an underwritten registration.  In the event such
a registration is an underwritten offering, the Company will enter into an
underwriting agreement with the managing underwriter or underwriters for such
offering (which managing underwriter or underwriters shall be an investment
banking firm or firms of national reputation designated by the Company and
satisfactory to the Stockholders holding a majority of the Registrable
Securities to be included in such registration), such agreement to contain such
terms as are customarily contained in agreements of such type.  Stockholders
selling Registrable Securities in such offering shall be party to such
underwriting agreement.

          (b) No Person may participate in any registration hereunder that is
underwritten unless such Person (i) agrees to sell such Person's securities on
the basis provided in any underwriting arrangements approved by the Person or
Persons entitled hereunder to approve such arrangements and (ii) completes and
executes all questionnaires, powers of attorney, indemnities, underwriting
agreements and other documents required under the terms of such underwriting
arrangements.

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     11.  Indemnification.
          ---------------

          (a) In connection with any offering of Registrable Securities pursuant
to Section 2 or 3 hereof, the Company agrees to indemnify, to the fullest extent
permitted by law, each Stockholder whose Registrable Securities are sold in such
offering, each of their officers and directors and each Person who controls such
Stockholder (within the meaning of the Securities Act) against all losses,
claims, damages, liabilities and expenses (including attorney's fees) arising
out of or based upon any untrue or alleged untrue statement of material fact
contained in any registration statement, prospectus or preliminary prospectus or
any amendment thereof or supplement thereto under which such Registrable
Securities were registered under the Securities Act (the "Registration
Materials") or any omission or alleged omission of a material fact required to
be stated therein or necessary to make the statements therein not misleading,
except insofar as such untrue statement or alleged untrue statement or omission
or alleged omission was made in such Registration Materials upon any written
information furnished in writing to the Company by such Stockholder.

          (b) Each Stockholder whose Registrable Securities are sold in any
offering pursuant to Section 2 or 3 hereof, severally but not jointly agrees to
indemnify, to the fullest extent permitted by law, the Company, the other
Stockholders whose Registrable Securities are sold in such offering, their
respective officers and directors and each other Person, if any, who controls
the Company or such other Stockholders (within the meaning of the Securities
Act) against all losses, claims, damages, liabilities and expenses (including
attorney's fees) caused by any untrue or alleged untrue statement of a material
fact contained in any Registration Materials or any omission or alleged omission
of a material fact required to be stated therein or necessary to make the
statements therein not misleading, in each case to the extent, but only to the
extent, that such untrue statement or alleged untrue statement or omission or
alleged omission was made in such Registration Materials in reliance upon any
written information furnished in writing to the Company by the Stockholder. In
no event shall the liability of any Stockholder hereunder be an amount greater
than the dollar amount of the proceeds received by such Stockholder upon the
sale of the Registrable Securities giving rise to such indemnification
obligation.

          (c) Each indemnified party shall give prompt notice to each
indemnifying party of any action threatened or commenced against it in respect
of which indemnity may be sought hereunder.  In case of any notice under this
indemnity agreement with respect to any loss, liability, claim, damage or
expense with respect to any claim made against an indemnified Person, the
indemnifying party shall be entitled to participate at its own expense in the
defense and such defense shall be conducted by counsel chosen by the
indemnifying party.  In no event shall an indemnifying party be liable for the
fees and expenses of more than one counsel for an indemnified party (in addition
to local counsel) in connection with any one action or separate but similar or
related actions in the same jurisdiction arising out of the same general
allegations or circumstances.

     12.  Transferees.  Any Person acquiring from the Stockholder or an
          -----------
Affiliate any Registrable Securities, except for transferees acquiring
Registrable Securities in an offering registered under the Securities Act or in
a sale made pursuant to Rule 144 under the Securities Act,

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may elect, within 30 days of the date of the transfer to it of such Registrable
Securities, to sign the signature page attached hereto as Annex A and delivering
an executed original copy of such signature page to the Company and thereby
become a party to this Agreement and be deemed a Stockholder under this
Agreement. Each such Stockholder shall be bound by the terms of this Agreement
and shall hold such Registrable Securities with all the rights conferred, and
subject to all obligations and restrictions imposed, hereby.

     13.  Miscellaneous.
          -------------

          (a) This Agreement contains the entire understanding of the parties
hereto with respect to its subject matter.  This Agreement supersedes all prior
agreements and understandings between the parties with respect to its subject
matter.   This Agreement may be amended and the observance of any term of this
Agreement may be waived (either generally or in a particular instance and either
retroactively or prospectively) only by a written instrument duly executed by
the Company and Stockholders holding a majority of the Registrable Securities;
provided, that, in the case of any waiver, such waiver need only be executed by
any Stockholders affected by such waiver.  Each Stockholder shall be bound by an
amendment or waiver authorized by this Section 13(a), whether or not any
Registrable Securities shall have been marked to indicate such consent.

          (b) All covenants and agreements in this Agreement by or on behalf of
any of the parties hereto will bind and inure to the benefit of the respective
successors and permitted assigns of the parties hereto whether so expressed or
not.

          (c) Whenever possible, each provision of this Agreement will be
interpreted in such manner as to be effective and valid under applicable law,
but if any provision of this Agreement is held to be prohibited by or invalid
under applicable law, such provision will be ineffective only to the extent of
such prohibition or invalidity, without invalidating the remainder of this
Agreement.

          (d) This Agreement may be executed in two or more counterparts,  any
one of which need not contain the signatures of more than one party, but all
such counterparts taken together will constitute one and the same Agreement.

          (e) The descriptive headings of this Agreement are inserted for
convenience only and do not constitute a part of this Agreement.

          (f) The interpretation and construction of this Agreement and all
matters relating hereto, shall be governed by the law of the State of Colorado
without regard to the conflicts of laws provisions of such state.

          (g) All notices, demands or other communications to be given or
delivered under or by reason of the provisions of this Agreement will be in
writing and will be deemed to have been given when delivered personally, by
facsimile or mailed by certified or registered mail, return receipt requested
and postage prepaid, or by courier guaranteeing overnight delivery as follows:

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               (i) If to any other Stockholder, at the most current address
given by such Stockholder to the Company; and

               (ii) If to the Company, at:

                    United International Holdings, Inc.
                    4643 South Ulster Street, Suite 1300
                    Denver, Colorado  80237
                    Attention:  General Counsel
                    Telephone No.:  (303) 770-4001
                    Facsimile No.:  (303) 770-4207

                    with a copy to:

                    Holme Roberts & Owen LLP
                    1700 Lincoln, Suite 4100
                    Denver, Colorado  80203
                    Attention: W. Dean Salter, Esq.
                    Telephone No.:  (303) 861-7000
                    Facsimile No.:  (303) 866-0200

     All such notices and communications shall be deemed to have been duly
given: at the time delivered by hand, if personally delivered; four business
days after being deposited in the mail, postage prepaid, if mailed; upon
confirmation of transmission, if by facsimile transmission; and on the next
business day if timely delivered to a courier guaranteeing' overnight delivery.

     IN WITNESS WHEREOF, the parties have duly signed this Agreement as of the
day and year first above written.


                                    UNITED INTERNATIONAL HOLDINGS, INC.
                                    -----------------------------------

                                    By: /s/ Ellen P. Spangler
                                        ---------------------
                                        Name: Ellen P. Spangler
                                        Title: Senior Vice President

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                                      RIORDAN COMMUNICATIONS LIMITED
                                      ------------------------------

                                      By: /s/ John F. Riordan
                                          --------------------
                                      Name:  J.F. Riordan
                                      Title:  Director

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                                    ANNEX A
                                    -------


     THE UNDERSIGNED hereby elects to become a party to the Registration Rights
Agreement dated as of April 8, 1999 initially between United International
Holdings, Inc. and the Stockholder named therein pursuant to Section 12 of such
Agreement.


                              [Name of Transferee]



                              By:
                                 ---------------------------------
                              Name:
                              Title:



Date:
     --------------------


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