SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549

                                    FORM 8-K
                                 CURRENT REPORT
                     Pursuant to Section 13 or 15(d) of the
                         Securities Exchange Act of 1934



                                  May 20, 2004
                                  ------------
                Date of Report (Date of earliest event reported)



                                CIENA Corporation
                                -----------------
             (Exact name of registrant as specified in its charter)


          Delaware                        0-21969                 23-2725311
(State or other jurisdiction       (Commission File No.)        (IRS Employer
     of incorporation)                                       Identification No.)

                 1201 Winterson Road, Linthicum, Maryland 21090
                 ----------------------------------------------
               (Address of principal executive offices) (Zip Code)



               Registrant's telephone number, including area code:
                                 (410) 865-8500
                                 --------------


                                 Not applicable
                                 --------------
          (Former name or former address, if changed since last report)


                             Exhibit Index on Page 2

The information in this Report, including the exhibit, is furnished under Item 12 of Form 8-K and, pursuant to General Instruction B.6. thereunder, is not "filed" for the purposes of Section 18 of the Securities Exchange Act of 1934 or otherwise subject to the liabilities of that section. Furthermore, the information in this Report, including the exhibit, is not incorporated by reference into the filings of the registrant under the Securities Act of 1933. Item 12 -- Regulation FD Disclosure (Information Provided Under Item 12 Results of Operations and Financial Condition) On May 20, 2004, CIENA Corporation issued a press release announcing its financial results for the fiscal quarter ended April 30, 2004. The text of the press release is furnished as Exhibit 99.1 to this Report. -2-

SIGNATURES Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned thereunto duly authorized. CIENA CORPORATION Dated: May 20, 2004 By: /s/ Russell B. Stevenson, Jr. --------------------------------- Senior Vice President, General Counsel and Secretary -3-

                                                                    Exhibit 99.1

CIENA Reports Second Quarter 2004 Results

    LINTHICUM, Md.--(BUSINESS WIRE)--May 20, 2004--CIENA(R)
Corporation (NASDAQ:CIEN), a leading global provider of innovative
networking solutions, today reported its second fiscal quarter results
for the period ending April 30, 2004. Revenue for the quarter totaled
$74.7 million, representing a 12.5% sequential increase and an
increase of 1.6% for the same period a year ago. On a generally
accepted accounting principles (GAAP) basis, CIENA's reported net loss
for the quarter was $76.2 million, or a net loss of $0.16 per share.
    "The last quarter was important for CIENA as we took significant
and deliberate steps in two key areas aimed at improving our business
in both the immediate and longer-term," said Gary Smith, CIENA's
president and CEO. "First, with the acquisitions of Catena Networks
and Internet Photonics, we have added products to help build CIENA
into a leading provider of service-delivery solutions. Second, we
initiated the next phase of strategic operating expense reductions
that will improve our cost structure and shorten the path to our
near-term goals of achieving cash flow breakeven and profitability."

    Second Quarter 2004 Highlights

    --  Ended the quarter with cash and short- and long-term
        investments valued at $1.46 billion, using cash of $60 million
        in the quarter.

    --  Announced expected annualized cost savings of $60 to $70
        million, including $55 to $65 million at the operating expense
        level, associated with closing the Company's San Jose, Calif.,
        facility and related headcount reductions.

    --  Announced customer wins spanning CIENA's networking solutions
        portfolio including:

        --  MCI's selection of CIENA as a strategic supplier for its
            new nationwide, ultra long-haul network.

        --  Verizon's choice of CIENA's multiservice switching
            solutions to enhance the efficiency of its nationwide
            enterprise data services.

        --  Red Electrica's deployment of CIENA solutions to expand
            its broadband services.

        --  An exclusive agreement with UK-carrier, THUS, for CIENA's
            multiservice solutions in metro and edge applications.

        --  Spanish Internet service provider, Arsys Internet's,
            selection of CIENA and reseller partner Laurel Networks,
            for a Broadband Remote Access Server (B-RAS) application.

    --  In addition, SBC recognized CIENA as an outstanding supplier
        for the superior performance of its DN 7000(TM) Series
        Multiservice Edge Switch.

    --  From a solutions perspective, CIENA announced and began
        deployments of the next-generation of its core networking
        capabilities with CoreStream(TM) Agility, designed to enable
        efficient delivery of high-growth broadband services, and also
        a new-generation CN 2000(TM) Storage Over SONET/SDH Platform
        to incorporate Dynamic Bandwidth Assignment capabilities and
        the latest ITU Generic Framing Procedure (GFP) standard.

    In addition, on May 3, 2004, just following completion of CIENA's
second fiscal quarter, the Company announced it had completed the
acquisitions of Catena Networks, Inc. and Internet Photonics, Inc.

    Non-GAAP Presentation

    In evaluating the operating performance of its business, CIENA's
management excludes certain charges or credits that are required by
GAAP. These items, which are identified in the table below, share one
or more of the following characteristics: they are unusual, and CIENA
does not expect them to recur in the ordinary course of its business;
they do not involve the expenditure of cash; they are unrelated to the
ongoing operation of the business in the ordinary course; or their
magnitude and timing is largely outside of the Company's control.



                                        Quarter Ended  6 Months Ended
                                        -------------- ---------------
                                        April 30, 2004 April  30, 2004
                                        -------------- ---------------
Item                                    (in thousands) (in thousands)
- ----                                    -------------- ---------------
Deferred stock compensation             $       1,902  $        4,746
Amortization of intangible assets               3,395           6,791
Accelerated amortization of leasehold
 improvements                                   1,649           1,649
Restructuring costs                             5,185           8,578
Recovery of use tax payments                   (1,931)         (1,931)
Recovery of doubtful accounts, net             (2,794)         (2,794)
Gain on equity investments, net                  (139)           (593)
Loss on extinguishment of debt                      -           8,216
Income tax benefit on adjusted net loss        24,402          45,437
                                        -------------- ---------------
                      Total Adjustments $      31,669  $       70,099
                                        ============== ===============

GAAP Net Loss                           $     (76,216) $     (152,924)
Adjusted for items above                       31,669          70,099
                                        -------------- ---------------
Non GAAP Net Loss                       $     (44,547) $      (82,825)
                                        ============== ===============


  Please see Appendix A for additional information about this table.


    These adjustments are not in accordance with GAAP, and making
these adjustments may not permit meaningful comparisons to other
companies.
    As of the quarter ended April 30, 2004, CIENA's weighted average
shares outstanding were approximately 475,189,000. Adjusting CIENA's
quarterly GAAP results as noted would reduce the Company's net loss in
its second fiscal quarter to $0.09 per share.
    For the six months ended April 30, 2004, CIENA's weighted average
shares outstanding were approximately 474,192,000. Adjusting CIENA's
six month GAAP results as noted would reduce the Company's net loss
for the period to $0.17 per share.

    Business Outlook

    "While it appears the industry has achieved a certain level of
stability, customers are maintaining an overall cautious and focused
approach to spending," said CIENA's Smith. "Spending in the core of
the network remains a secondary priority as service providers focus on
getting more users on to their networks and generating more revenue
from that traffic. With the addition of new service delivery platforms
from Catena and Internet Photonics, CIENA is better positioned to
benefit from that focus.
    "In part as a result of our broader portfolio reach, we expect
revenue for our third fiscal quarter will increase by as much as 30
percent from our fiscal second quarter revenue," said Smith.

    Live Web Broadcast of Q2 Results

    CIENA will host a discussion of this morning's announcements with
investors and financial analysts today, Thursday, May 20, 2004 at 8:30
a.m. (Eastern). The live broadcast of the discussion will be available
via CIENA's homepage at www.CIENA.com. An archived version of the
discussion will be available shortly following the conclusion of the
live broadcast on the Investor Relations page of CIENA's website at:
www.CIENA.com/investors.

    NOTE TO INVESTORS

    This press release contains certain forward-looking statements
based on current expectations, forecasts and assumptions of CIENA (the
Company) that involve risks and uncertainties. Forward-looking
statements in this release, including but not limited to: we initiated
the next phase of strategic operating expense reductions that will
improve our cost structure and shorten the path to our near-term goals
of achieving cash flow breakeven and profitability; while it appears
the industry has achieved a certain level of stability, customers are
maintaining an overall cautious and focused approach to spending;
spending in the core of the network remains a secondary priority as
service providers focus on getting more users on to their networks and
generating more revenue from that traffic; with the addition of new
service delivery platforms from Catena and Internet Photonics, CIENA
is better positioned to benefit from that focus; and, in part as a
result of our broader portfolio reach, we expect revenue for our third
fiscal quarter will increase by as much as 30 percent from our fiscal
second quarter revenue, are based on information available to the
Company as of the date hereof. The Company's actual results could
differ materially from those stated or implied in such forward-looking
statements, due to risks and uncertainties associated with the
Company's business, which include the risk factors disclosed in the
Company's Report on Form 10-Q, which we expect to file with the
Securities and Exchange Commission on May 20, 2004. Forward-looking
statements include statements regarding the Company's expectations,
beliefs, intentions or strategies regarding the future and can be
identified by forward-looking words such as "anticipate," "believe,"
"could," "estimate," "expect," "intend," "may," "should," "will," and
"would" or similar words. The Company assumes no obligation to update
the information included in this press release, whether as a result of
new information, future events or otherwise.



                           CIENA CORPORATION
                 CONSOLIDATED STATEMENTS OF OPERATIONS
                 (in thousands, except per share data)
                              (unaudited)


                                Quarter Ended      Six Months Ended
                             ------------------- ---------------------
                             April 30, April 30, April 30,  April 30,
                               2003      2004      2003       2004
                             --------- --------- ---------- ----------

Revenues:
  Products                   $ 63,399  $ 62,422  $ 124,620  $ 117,096
  Services                     10,141    12,277     19,394     24,017
                             --------- --------- ---------- ----------
Total revenue                  73,540    74,699    144,014    141,113

Costs:
  Products                     40,406    56,289     79,983     90,849
  Services                     14,919    10,188     29,551     21,489
                             --------- --------- ---------- ----------
Total cost of goods sold       55,325    66,477    109,534    112,338
                             --------- --------- ---------- ----------
  Gross profit                 18,215     8,222     34,480     28,775
                             --------- --------- ---------- ----------
Operating expenses:
  Research and development     52,193    46,479    105,927     93,656
  Selling and marketing        25,663    25,075     52,268     50,543
  General and administrative    8,066     5,992     22,772     13,083
  Deferred stock
   compensation costs:
    Research and development    3,406     1,408      7,204      3,613
    Selling and marketing         676       415      1,435        933
    General and
     administrative               346        79        720        200
  Amortization of intangible
   assets                       3,421     3,395      6,975      6,791
  Restructuring costs           2,724     5,185      2,724      8,578
  Recovery of use tax
   payments                         -    (1,931)         -     (1,931)
  Recovery of doubtful
   accounts, net                    -    (2,794)         -     (2,794)
                             --------- --------- ---------- ----------
    Total operating expenses   96,495    83,303    200,025    172,672
                             --------- --------- ---------- ----------

Loss from operations          (78,280)  (75,081)  (165,545)  (143,897)

Interest and other income,
 net                           11,131     5,614     24,432     13,292

Interest expense               (8,061)   (6,473)   (20,264)   (13,857)

Gain (loss) on equity
 investments, net                   -       139        (10)       593

Loss on extinguishment of
 debt                               -         -    (20,606)    (8,216)
                             --------- --------- ---------- ----------

Loss before income taxes      (75,210)  (75,801)  (181,993)  (152,085)

Provision for income taxes        251       415        610        839
                             --------- --------- ---------- ----------

Net loss                     $(75,461) $(76,216) $(182,603) $(152,924)
                             ========= ========= ========== ==========

Basic and diluted net loss
 per common share and
 dilutive potential common
 share                       $  (0.17) $  (0.16) $   (0.42) $   (0.32)
                             ========= ========= ========== ==========

Weighted average basic        433,932   475,189    433,330    474,192
 common and dilutive         ========= ========= ========== ==========
 potential common shares
 outstanding




                          CIENA CORPORATION
                     CONSOLIDATED BALANCE SHEETS
                  (in thousands, except share data)
                             (unaudited)


                                               October 31,  April 30,
                                                  2003        2004
                                               ----------- -----------
                    ASSETS
Current assets:
  Cash and cash equivalents                    $  309,665  $  218,145
  Short-term investments                          796,809     824,929
  Accounts receivable, net                         43,600      38,593
  Inventories, net                                 44,995      34,457
  Prepaid expenses and other                       34,334      42,388
                                               ----------- -----------
    Total current assets                        1,229,403   1,158,512
Long-term investments                             519,744     416,199
Equipment, furniture and fixtures, net            114,930     100,123
Goodwill                                          336,039     335,974
Other intangible assets, net                      108,408      99,681
Other long-term assets                             69,641      67,346
                                               ----------- -----------
    Total assets                               $2,378,165  $2,177,835
                                               =========== ===========

     LIABILITIES AND STOCKHOLDERS' EQUITY

Current liabilities:
  Accounts payable                             $   44,402  $   38,532
  Accrued liabilities                              98,926      89,797
  Restructuring liabilities                        14,378      12,605
  Unfavorable lease commitments                     9,380       9,467
  Income taxes payable                              4,640       5,596
  Deferred revenue                                 14,473      16,373
                                               ----------- -----------
    Total current liabilities                     186,199     172,370
Long-term deferred revenue                         14,547      16,964
Long-term restructuring liabilities                52,164      45,888
Long-term unfavorable lease commitments            61,312      56,362
Other long-term obligations                         2,698       2,741
Convertible notes payable                         730,428     690,000
                                               ----------- -----------
    Total liabilities                           1,047,348     984,325
                                               ----------- -----------
Commitments and contingencies
Stockholders' equity:
  Preferred stock - par value $0.01;
   20,000,000 shares authorized; zero shares
   issued and outstanding                               -           -
  Common stock - par value $0.01; 980,000,000
   shares authorized; 473,214,856 and
   476,940,672 shares issued and outstanding        4,732       4,769
  Additional paid-in capital                    4,861,182   4,874,950
  Deferred stock compensation                      (9,664)     (4,572)
  Notes receivable from stockholders                 (448)       (448)
  Accumulated other comprehensive income
   (loss)                                           2,447        (833)
  Accumulated deficit                          (3,527,432) (3,680,356)
                                               ----------- -----------
                                                1,330,817   1,193,510
                                               ----------- -----------
  Total liabilities and stockholders' equity   $2,378,165  $2,177,835
                                               =========== ===========


    Appendix A

    The adjustments management makes in analyzing CIENA's first
quarter fiscal 2004 GAAP results are as follows:

    --  Deferred stock compensation costs - a non-cash expense largely
        unrelated to normal operations, and which arises under GAAP
        accounting from the assumption of unvested stock options
        issued by any companies we acquire.

    --  Amortization of intangible assets - a non-cash expense
        unrelated to normal operations arising from acquisitions of
        intangible assets, principally developed technology acquired
        in the Cyras, ONI, WaveSmith, and Akara acquisitions, which
        CIENA is required to amortize over its expected useful life.

    --  Accelerated amortization of leasehold improvements - a
        non-cash expense related to the planned closing of our San
        Jose, California facility.

    --  Restructuring costs - non-recurring charges, unrelated to
        normal operations, incurred as the result of reducing the size
        of the Company's operations to align its resources with the
        reduced size of the telecommunications market as well as the
        result of targeting new segment opportunities within the
        overall market.

    --  Recovery of use tax payments - a non-recurring gain unrelated
        to normal operations.

    --  Recovery of doubtful accounts, net - a non-recurring gain
        unrelated to normal operations due to payment received from a
        customer from which payment was previously deemed doubtful due
        to the customer's financial condition.

    --  Gain on equity investments, net - a non-recurring gain
        unrelated to normal operations.

    --  Loss on extinguishment of debt - a non-recurring expense,
        unrelated to normal operations.

    --  Income tax benefit on adjusted net loss - the income tax
        charge or benefit on the adjusted net loss, which is a
        necessary adjustment for consistency. The Company currently
        has a full valuation allowance for GAAP reporting purposes and
        accordingly does not recognize a tax benefit for losses
        generated.

    ABOUT CIENA

    CIENA Corporation delivers innovative network solutions to the
world's largest service providers and enterprises, increasing the
cost-efficiency of current services while enabling the creation of new
carrier-class data services built upon the existing network
infrastructure. Additional information about CIENA can be found at
www.ciena.com.

    CONTACT: CIENA Corporation
             Investor Contacts:
             Suzanne DuLong or Jessica Towns, 888-243-6223
             ir@ciena.com
               or
             Press Contacts:
             Aaron Graham or Nicole Anderson, 877-857-7377
             pr@ciena.com