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

       Date of Report (Date of earliest event reported):  March 10, 2000

                                  CMGI, Inc.
             -----------------------------------------------------
            (Exact name of registrant as specified in its charter)

            Delaware               000-23262           04-2921333
     --------------------      ----------------   --------------------
    (State or other juris-       (Commission         (IRS Employer
  diction of incorporation)      File Number)     Identification No.)

         100 Brickstone Square, Andover, MA               01810
         ----------------------------------             ----------
      (Address of principal executive offices)          (Zip Code)

Registrant's telephone number, including area code:  (978) 684-3600

                                      N/A
         -------------------------------------------------------------
         (Former name or former address, if changed since last report)


Item 5.  Other Events.
         -------------

yesmail.com, inc.
- -----------------

     On March 10, 2000, CMGI, Inc. ("CMGI" or the "Company") completed the
transactions contemplated by the Agreement and Plan of Merger, dated as of
December 14, 1999 (the "yesmail Merger Agreement"), among itself, Mars
Acquisition, Inc., a wholly owned subsidiary of the Company (the "yesmail Sub"),
and yesmail.com, inc. ("yesmail").  Pursuant to the yesmail Merger Agreement,
CMGI will issue .2504 shares of CMGI common stock  for each share of yesmail
common stock outstanding on March 10, 2000, and the yesmail Sub merged with and
into yesmail, with yesmail surviving as a wholly owned subsidiary of CMGI.  The
Company's press release announcing the closing of this transaction is filed as
Exhibit 99.1 hereto.

uBid, Inc.
- ----------

     On April 28, 2000, CMGI completed the transactions contemplated by the
Agreement and Plan of Merger and Reorganization, dated as of February 9, 2000
(the "uBid Merger Agreement"), among itself, Senlix Corporation, a wholly owned
subsidiary of the Company (the "uBid Sub"), and uBid, Inc. ("uBid").  Pursuant
to the uBid Merger Agreement, CMGI will issue .2628 shares of CMGI common stock
for each share of uBid common stock outstanding on April 28, 2000, and the uBid
Sub merged with and into uBid, with uBid surviving as a wholly owned subsidiary
of CMGI.  The Company's press release announcing the closing of this transaction
is filed as Exhibit 99.2 hereto.


Item 7.  Financial Statements, Pro Forma Financial Information and Exhibits.
         -------------------------------------------------------------------

(c)  Exhibits.

Exhibit No.    Description
- -----------    -----------

   99.1        Press release, dated March 13, 2000, announcing the completion
               of the acquisition of yesmail.com, inc. by CMGI, Inc.

   99.2        Press release, dated May 1, 2000, announcing the completion
               of the acquisition of uBid, Inc. by CMGI, Inc.

                                       2


                                   SIGNATURE

     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 hereunto duly authorized.

Date: May 25, 2000                CMGI, Inc.
                                  ----------
                                  (Registrant)



                                  By:  /s/ Andrew J. Hajducky, III
                                  --------------------------------
                                  Andrew J. Hajducky III
                                  Executive Vice President, Chief Financial
                                  Officer and Treasurer

                                       3


                                 EXHIBIT INDEX

Exhibit No.    Description
- -----------    -----------

   99.1        Press release, dated March 13, 2000, announcing the completion
               of the acquisition of yesmail.com, inc. by CMGI, Inc.

   99.2        Press release, dated May 1, 2000, announcing the completion
               of the acquisition of uBid, Inc. by CMGI, Inc.

                                       4


                                                                    EXHIBIT 99.1

PRESS CONTACTS:

Catherine Taylor               Deidre Moore                  Jim Carini
CMGI Investor Relations        CMGI Public Relations         yesmail.com
978-684-3540                   978-684-3655                  847-918-6379
ctaylor@cmgi.com               dmoore@cmgi.com               jimc@yesmail.com
- ----------------               ---------------               ----------------

                        CMGI COMPLETES ACQUISITION OF
                                  YESMAIL.COM

   PLANS TO LEVERAGE E-MAIL MARKETING LEADER'S 8 MILLION REGISTERED USERS TO
                 IMPROVE MONETIZATION ACROSS THE CMGI NETWORK

ANDOVER, MASS. AND VERNON HILLS, ILL., MARCH 13, 2000 - CMGI, Inc. (Nasdaq:
CMGI) announced today that it has completed its acquisition of yesmail.com
(Nasdaq: YESM), a leading outsourcer of permission email marketing technologies
and services. Under the approved terms of the merger, CMGI will issue .2504
shares of CMGI common stock for every share of yesmail.com common stock held on
March 10, 2000. Effective immediately, yesmail.com becomes a majority-owned
operating company of CMGI, joining CMGI's fast-growing arsenal of interactive
marketing and advertising properties, including Engage (and its subsidiaries
I/PRO and AdKnowledge), Adsmart, AdForce and Flycast.

"When we announced our agreement to acquire yesmail.com three months ago, we
talked extensively about the synergies and benefits the two companies could
bring to one another, and the entire CMGI network. These opportunities are even
bigger today as we begin to more formally integrate yesmail.com's opt-in
marketing services for the benefit of our content and e-commerce companies,
including new, pending acquisitions such as uBid.com," said David Andonian,
president of corporate development for CMGI. "We're excited about the
opportunities ahead and look forward to leveraging yesmail's 8 million
registered users and proven marketing expertise to improve monetization across
the network."

Dave Tolmie, yesmail.com CEO and president added, "We are extremely pleased that
our addition to the CMGI network of companies is complete. We look forward to
working closely with CMGI's leading marketing and advertising companies to
provide the most comprehensive interactive solution available to marketers."

Since the acquisition was announced December 14, 1999, yesmail.com has continued
to experience rapid growth. During the past three months, YesMail membership has
doubled to 8 million and is currently growing by more than 1 million members per
month on average. yesmail.com has also added 32 new Network Partners, including
Egghead.com and TRIP.com, for a current total of 90 YesMail Network Partners.
Collectively, these partners represent 190 individual Web sites.

yesmail.com's revenue for the fourth quarter ended December 31, 1999 was $8.2
million, a 114% sequential increase over the $3.8 million reported for the third
quarter. Total revenue for the year ended December 31, 1999 reached $15.6
million compared with $4.6 million in 1998.

ABOUT YESMAIL.COM
yesmail.com is the premier outsourcer of permission e-mail marketing
technologies and services, providing a total Customer Value Management solution
for its clients - from acquisition to retention and ongoing relationship
management. The YesMail Network(TM) is the Web's first permission-based customer
acquisition and retention engine, enabling YesMail's expert Relationship
Managers to target prospects, personalize messages, deliver campaigns, track and


analyze results, customize responses and generate reports for marketers in real
time. YesMail's proprietary direct marketing software, scalable infrastructure
and experienced strategists deliver a total outsourced solution to maximize
customer value for eMarketers. For more information, contact www.yesmail.com,
1-888-932-8600 or info@yesmail.com.

ABOUT CMGI AND CMGI@VENTURES
With more than 65 companies, CMGI, Inc. (Nasdaq: CMGI) represents the largest,
most diverse network of Internet businesses in the world, including both CMGI
operating companies and synergistic investments made through its venture capital
affiliate, CMGI@Ventures. CMGI leverages the technologies; content and market
reach of its extended family of companies to foster rapid growth and industry
leadership across its network and the larger Internet Economy. Compaq, Intel,
Microsoft, Pacific Century CyberWorks and Sumitomo hold minority positions in
CMGI.

CMGI's majority-owned operating companies include Engage Technologies (Nasdaq:
ENGA), NaviSite (Nasdaq: NAVI), 1ClickBrands, 1stUp.com, Activate.net, AdForce,
Adsmart, AltaVista, CMGI Solutions, Equilibrium, Flycast, iCAST, MyWay.com,
NaviNet, SalesLink, Tribal Voice and yesmail.com. CMGI@Ventures has ownership
interests in 48 Internet companies, including Lycos, Inc. (Nasdaq: LCOS),
Critical Path (Nasdaq: CPTH), Silknet (Nasdaq: SILK), MotherNature.com (Nasdaq:
MTHR), Ventro (Nasdaq: VNTR) and Vicinity (Nasdaq: VCNT). CMGI's corporate
headquarters is at 100 Brickstone Square, Andover, MA 01810, Tel: 978-684-3600.
CMGI@Ventures has offices there as well as at 3000 Alpine Road, Menlo Park, CA
94028. For additional information and a full listing of the CMGI and
CMGI@Ventures companies, see http://www.cmgi.com and http://www.ventures.com.


                                     # # #

This release contains forward-looking statements based on current expectations
or beliefs, as well as a number of assumptions about future events, and these
statements are subject to important factors and uncertainties that could cause
actual results to differ materially from those described in the forward-looking
statements. The forward-looking statements in this release address a variety of
subjects including, for example, the expected benefits resulting from the
acquisition of yesmail.com by CMGI, the expected growth in CMGI's advertising
and marketing business, the expected benefits of yesmail's relationships with
third parties, including AdForce, Flycast, Engage and Adsmart, and the expected
functionality of yesmail's product offerings. The following factors, among
others, could cause actual results to differ materially from those described in
these forward-looking statements: yesmail's business may not be successfully
integrated with the business of CMGI; yesmail's technologies and products may
not successfully interoperate with those of third parties; the adoption of new
laws and regulations affecting the provision of Internet advertising services,
including laws and regulations covering privacy, pricing and content; and
increased competition and technological changes in the industries in which CMGI
and yesmail compete. For a detailed discussion of these and other cautionary
statements, please refer to CMGI's filings with the Securities and Exchange
Commission, including CMGI's Annual Report on Form 10-K for the most recently
ended fiscal year.

                                       2


                                                                    EXHIBIT 99.2

PRESS CONTACTS:

  For CMGI:                         For uBid.com:
  Kim Robinson                      Nevenka Todorovic
  CMGI Public Relations             uBid.com
  (978) 684-3127                    (773) 272-4449
  krobinson@cmgi.com                nevenkat@ubid.com
  ------------------                -----------------
  Catherine Taylor                  Bret Werner/Ted Fragulis
  CMGI Investor Relations           Alan Taylor Communications
  (978) 684-3540                    (212) 714-1280
  ctaylor@cmgi.com                  bret@alantaylor.com
  ----------------                  -------------------
                                    tfragulis@alantaylor.com
                                    ------------------------

                      CMGI COMPLETES UBID.COM ACQUISITION

     INTEGRATION OF E-COMMERCE AUCTION SITE TO LEVERAGE SYNERGIES ACROSS
                                 CMGI NETWORK

 CMGI ON TRACK TO CLOSE FISCAL 2000 WITH ANNUAL REVENUE RUN RATE OF $1 BILLION

ANDOVER, MA AND CHICAGO, IL, MAY 1, 2000 - CMGI, Inc. (NASDAQ: CMGI), the
world's largest and most diverse network of Internet companies, announced today
that it has completed its acquisition of uBid, Inc. (NASDAQ: UBID), a leading e-
commerce auction site. Effective immediately, uBid joins CMGI as a majority-
owned operating company. Under the terms of the agreement, CMGI will issue .2628
shares of CMGI common stock for every share of uBid common stock held on April
28, 2000.

"The addition of uBid to the CMGI network underscores our commitment to
strengthening and expanding our business-to-consumer (B2C) and business-to-
business (B2B) e-commerce capabilities," said David Andonian, president,
corporate development for CMGI. "It also permits CMGI to leverage uBid's
services for new, expanded opportunities within the network, including the
integration of auction and merchandising capabilities into our enterprise
solutions, while offering uBid a powerful new set of partners from which to
accelerate its already impressive growth and revenue performance."

As recently reported, uBid's revenues for the first quarter ended March 31, 2000
grew to $86 million, up 150 percent over first quarter 1999 revenues.
Additionally, its base of registered users increased to 1.2 million compared to
the 378,000 users at the end of the first quarter of 1999. Since the acquisition
was announced February 10, 2000, uBid.com has continued to experience rapid
growth and has opened an additional customer care center in Danville, Illinois
to handle its expanding customer base. With the addition of uBid to the CMGI
network, CMGI continues to believe it will be able to achieve its goal of an
annual run rate of $1 billion in revenue by the end of its fiscal year.

"CMGI is a powerhouse and we are happy to be a part of its diverse network,"
said Greg Jones, CEO, uBid.com. "The relationship will open the door to
opportunities, allowing uBid.com to continue growing and establishing ourselves
as an industry leader. In addition to greatly increasing our reach in the
consumer marketplace, the potential for strategic relationships with CMGI
network companies will lead to new sources of unique merchandise, as well as
powerful new distribution outlets for our auction technology platform."

uBid offers brand-name products to both consumers and businesses providing
visitors the opportunity to set their own prices on popular products at
significant discounts from prices found in traditional channels. In addition,
uBid.com auctions provide leading suppliers such as Sony, IBM, Hewlett-Packard,
Canon, Epson and Harman Kardon, with an inexpensive and highly


efficient channel for selling excess or unique items on a timely basis, while
preserving their existing distribution channels.

ABOUT CMGI AND CMGI@VENTURES
With more than 70 companies, CMGI, Inc. (Nasdaq: CMGI) represents the largest,
most diverse network of Internet companies in the world, including both CMGI
operating companies and synergistic investments made through its venture capital
affiliate, CMGI@Ventures. CMGI leverages the technologies, content and market
reach of its extended family of companies to foster rapid growth and industry
leadership across its network and the larger Internet Economy. Compaq, Intel,
Microsoft, Pacific Century CyberWorks and Sumitomo hold minority positions in
CMGI.

CMGI's majority-owned operating companies include Engage (Nasdaq: ENGA),
NaviSite (Nasdaq: NAVI), 1ClickBrands, 1stUp.com, Activate, AdForce, Adsmart,
AltaVista, CMGion, CMGI Solutions, Equilibrium, Flycast, iCAST, MyWay.com,
NaviPath, uBid, SalesLink, Tribal Voice and yesmail.com. CMGI@Ventures has
ownership interests in 57 companies, including Lycos, Inc. (Nasdaq: LCOS),
Critical Path (Nasdaq: CPTH), MotherNature.com (Nasdaq: MTHR), Ventro (Nasdaq:
VNTR) and Vicinity (Nasdaq: VCNT).

CMGI's corporate headquarters is located at 100 Brickstone Square, Andover, MA
01810. CMGI@Ventures has offices there, as well as at 3000 Alpine Road, Menlo
Park, CA 94028. For additional information, see http://www.cmgi.com and
http://www.ventures.com.

ABOUT UBID.COM
uBid.com, with headquarters in Chicago, is a leading on-line auction and e-
commerce site that offers consumers and small- to mid-sized businesses the
opportunity to "set the price" on a wide range of brand name merchandise through
live-action bidding using sophisticated auction technology. The company's
Internet auctions feature a rotating selection of more than 6,700 items in each
daily auction. Consumers can browse in more than 12 different product
categories, including: computers, consumer electronics, home and leisure, sports
and recreation, jewelry and gifts, apparel, appliances, art, travel and events,
home improvement products, monitors and printers, and off-lease computer
equipment.

With more than 1 million registered users, uBid.com is committed to providing
all customers with the highest quality auction experience on the Internet and
offers supplier warranties on most consumer products. uBid.com also meets Better
Business Bureau Online standards, which gives customers the confidence and
security to bid safely online.

For more information, visit the company's Web site at www.ubid.com.

                                     # # #

This release contains forward-looking statements based on current expectations
or beliefs, as well as a number of assumptions about future events, and these
statements are subject to important factors and uncertainties that could cause
actual results to differ materially from those described in the forward-looking
statements. The forward-looking statements in this release address a variety of
subjects including, for example, the expected benefits resulting from the
acquisition of uBid.com by CMGI, the expected ability of CMGI to leverage uBid's
services, the expected future growth of uBid and the expected growth and
revenues of CMGI and its operating companies. The following factors, among
others, could cause actual results to differ materially from those described in
these forward-looking statements: uBid's business may not be successfully
integrated with the business of CMGI; uBid's technologies and products may not
successfully interoperate with those of third parties; CMGI's growth and success
depends upon continued and increased demand for and market acceptance of CMGI's
and its operating companies' web sites and the Internet in general; and
increased competition and technological changes in the industries in which CMGI
and uBid compete. For detailed discussion of these and

                                       2


other cautionary statements, please refer to CMGI's filings with the Securities
and Exchange Commission, including CMGI's Annual Report on Form 10-K for the
most recently ended fiscal year.

                                       3