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                                                                EXHIBIT 10.18(a)

                         AMENDMENT NO. 1 TO SUBLEASE AND
                           SUPPORT SERVICES AGREEMENT

AGREEMENT, dated as of July 1, 1999 between Rittenhouse Financial Services,
Inc., a Delaware corporation ("RFS"), and The Rittenhouse Trust Company, a trust
company and commercial bank organized under the laws of the Commonwealth of
Pennsylvania ("RTC"). Capitalized terms used but not otherwise defined in this
Agreement shall have the meanings ascribed to them in the Sublease (as defined
below) or the Support Services Agreement (as defined below), as the case may be.

WHEREAS, RFS and RTC have entered into a Sublease, dated as of August 31, 1997
(the "Sublease"), and a Support Services Agreement, dated as of August 31, 1997
(the "Support Services Agreement");

WHEREAS, pursuant to the Sublease, since August 31, 1997, RTC has subleased from
RFS certain office space leased by RFS at Two Radnor Corporate Center, Radnor,
Pennsylvania;

WHEREAS, pursuant to the Support Services Agreement, since August 31, 1997, RFS
has made available to RTC certain support services used by RTC in the operation
of its business; and

WHEREAS, RTC has moved its business operations to new premises in Radnor
Corporate Center as a result of its desire to expand, RFS desires to utilize the
space that RTC has vacated, and RFS and RTC desire to amend the terms of the
Sublease and the Support Services Agreement in connection therewith;

NOW THEREFORE, in consideration of the foregoing recitals, the mutual promises
and agreements hereinafter set forth, and for other good and valuable
consideration, the receipt and sufficiency of which are hereby acknowledged, RFS
and RTC hereby agree as follows:

1.   Sublease. The Sublease shall terminate and be of no further force or effect
     (except as provided below with respect to Section 11 of the Sublease) as
     of May 17, 1999 (the "Sublease Termination Date"). RFS shall have no
     obligation to make any portion of the Premises available to RTC for its
     use, and RTC shall have no obligation to pay to RFS any Rent in respect of
     any period, after the Sublease Termination Date. This Agreement shall not
     affect in any way any rights that RFS or RTC may have against the other
     under the Sublease in respect of any actions or events occurring prior to
     the Sublease Termination Date or pursuant to


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     the indemnification provisions of Section 11 of the Sublease. RTC will pay
     Rent to RFS in respect of the period ending on the Sublease Termination
     Date (on a pro-rated basis) in accordance with the past practice of the
     parties. RFS shall notify the Landlord of the termination of the
     Sublease promptly following the Sublease Termination Date.

2.   Support Services Agreement. From and after the Sublease Termination Date,
     Sections 1, 4 and 14 of the Support Services Agreement shall be amended in
     respect of the services to be made available by RFS to RTC thereunder, the
     fees to be paid by RTC to RFS thereunder, and the term of such agreement,
     and replaced in their entirety by the provisions set forth below in
     Paragraphs 3 through 6. The Support Services Agreement, as amended by this
     Agreement, is referred to herein as the "Amended Support Services
     Agreement."

3.   Provided Services. Notwithstanding anything to the contrary contained in
     the Support Services Agreement, from and after the Sublease Termination
     Date, RFS will make available to RTC only the support services set forth on
     Schedule I hereto in accordance with the practices in effect on the date
     hereof or as otherwise specifically set forth in Schedule 1. From and after
     the Sublease Termination Date, RTC will have no obligation to make any
     support services available to RFS.

4.   Fees. Notwithstanding anything to the contrary contained in the Support
     Services Agreement, in consideration of the services to be provided under
     the Amended Support Services Agreement, RTC shall pay to the parent company
     of RFS, The John Nuveen Company ("JNC"), or an affiliate designated by JNC,
     in lieu of the Fixed Annual Fee set forth in the Support Services
     Agreement, an amount equal to six million four hundred twenty-four thousand
     two hundred twenty dollars ($6,424,220), which shall be payable in one
     installment of one million one hundred fifty-six thousand eight hundred
     twenty dollars ($1,156,820) on July 1, 1999 and in five equal quarterly
     installments of one million fifty-three thousand four hundred eighty
     dollars ($1,053,480) on the first business day of each calendar quarter,
     beginning October 1, 1999 and ending October 2, 2000 in each case by wire
     transfer of immediately available funds (the "Revised Fixed Fee"). The
     Revised Fixed Fee shall be payable regardless of whether and to what extent
     any RFS provided services are utilized by RTC hereunder during any calendar
     quarter to which a Revised Fixed Fee payment relates. In consideration of
     the services to be provided by RFS under this Agreement, RTC shall also pay
     to RFS the fee or other charge set forth opposite each such provided
     service on Schedule 1 in respect of RFS provided services actually provided
     and received by RTC during a billing period hereunder, and each RFS
     provided service will be invoiced to RTC in accordance with past practices.

5.   Contiguous Office Space. The requirement to pay fees payable under the
     Amended Support Services Agreement shall not be related in any way to the
     Sublease or to the location of RTC's business operations in space
     contiguous to that of RFS. RFS shall have no obligation to secure
     contiguous office space for



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     RTC in the event that RFS moves its business operations or acquires
     additional office space.

6.   Term. (a) Notwithstanding anything to the contrary contained in the Support
     Services Agreement, the Amended Support Services Agreement shall terminate,
     and RFS shall cease to be obligated to provide services, on the earlier of
     (i) December 31, 2000, (ii) an RTC Default as described in paragraph (b)
     below, and (iii) a material default by RFS hereunder, unless such default
     has been cured by RFS to the reasonable satisfaction of RTC within 30 days
     after receipt of written notice of default from RTC. In the event that the
     Amended Support Services Agreement would otherwise terminate on December
     31, 2000 in accordance with clause (i) of the preceding sentence, RTC shall
     have the right to extend such date to December 31, 2001 by delivering
     written notice of the desire to so extend to RFS no later than November 30,
     2000, together with a payment of one hundred dollars for such extension.
     Upon termination of the Amended Support Services Agreement all payment
     obligations of RTC shall cease except for any accrued and unpaid
     liabilities for the Revised Fixed Fee, for services previously rendered
     and, if applicable, any payment described in paragraph (c) below.

     (b) "RTC Default" means (i) a material default by RTC hereunder, unless
     such default has been cured by RTC to the reasonable satisfaction of RFS
     within 30 days after receipt of written notice of such default, (ii) a
     majority of the outstanding capital stock of RTC ceases to be owned by
     George W. Connell, or a Permitted Transferee (as defined in the
     Inter-Company Agreement among RTC, RFS, JNC and George W. Connell) or (iii)
     the sale, exchange, transfer or other disposition of any outstanding
     capital stock of RTC to a competitor of JNC.

     (c) In the event the Amended Support Services Agreement is terminated
     pursuant to an RTC Default, RTC shall make payment within five business
     days to JNC or an affiliate of JNC by wire transfer of immediately
     available funds of an amount equal to the present value (applying a
     discount rate equal to the then prevailing prime rate of interest announced
     by Morgan Guaranty Trust Company of New York) of the Revised Fixed Fee
     amounts which have not been theretofore paid. In the event of the
     termination of the Amended Support Services Agreement for any reason other
     than (i) an RTC Default or (ii) so long as there has been no continuing RTC
     Default and so long as RTC has not materially breached any of the
     Transaction Documents that is continuing, RFS's willful breach of its
     obligation under the Amended Support Services Agreement to provide
     services, RTC shall continue to pay the Revised Fixed Fee.

7.   Further Assurances. RFS and RTC agree to work together in good faith to
     ensure a smooth transition of the RTC business into new office space and to
     avoid confusion of customers or service providers relating to the
     similarity of the RFS and RTC names. In particular, the parties will work
     together and cooperate in connection with their respective mail room,
     receptionist and record management



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     personnel to take all necessary actions to insure a smooth transition in
     separation of the office space and of the previously shared office
     management functions. The parties also agree to work together to properly
     separate all commingled files held on location or offsite.

8.   No other Changes. Except as modified as set forth above, the provisions of
     the Support Services Agreement shall remain in full force and effect. This
     Agreement shall not affect in any way any of the terms of the agreements
     entered into by RFS and RTC at the time of the acquisition of RFS by JNC or
     subsequent thereto, other than the Sublease and the Support Services
     Agreement.

IN WITNESS WHEREOF, the parties hereto, being duly authorized, have duly
executed and delivered this Agreement.

                                            RITTENHOUSE FINANCIAL SERVICES, INC.

                                            By:
                                               --------------------------------
                                                  Name: Alan G. Berkshire
                                                  Title: Vice President

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

                                            THE RITTENHOUSE TRUST COMPANY

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

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

                                            THE JOHN NUVEEN COMPANY

                                            By:
                                               --------------------------------
                                                   Name: Alan G. Berkshire
                                                   Title: Senior Vice President

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



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