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                                                                       Exhibit 5
                   [Letterhead of Wilmer, Cutler & Pickering]

                                   May 2, 2003

Danaher Corporation
2099 Pennsylvania Avenue, 12th Floor
Washington, D.C. 20006-1813

Ladies and Gentlemen:

     We have acted as securities counsel for Danaher Corporation, a Delaware
corporation (the "Company"), in connection with its filing with the Securities
and Exchange Commission (the "Commission"), under the Securities Act of 1933, as
amended (the "Securities Act"), of a combined Registration Statement on Form S-3
and Post-Effective Amendment No. 1 to Registration Statement No. 333-83186
(collectively, the "Registration Statement"), with respect to the offering and
issuance from time to time by the Company, as set forth in the combined
prospectus pursuant to Rule 429 contained in the Registration Statement (the
"Prospectus") and as to be set forth in one or more supplements to the
Prospectus (each such supplement, a "Prospectus Supplement"), of up to
$1,000,000,000 aggregate initial offering price, and any such additional amounts
as may be registered pursuant to Rule 462(b) promulgated under the Securities
Act, of (1) one or more series of the Company's debt securities, which may be
senior or subordinated (the "Debt Securities"), (2) shares of the Company's
preferred stock, no par value (the "Preferred Stock"), (3) shares of the
Company's common stock, par value $0.01 per share (the "Common Stock"), (4)
warrants to purchase Debt Securities, Preferred Stock or Common Stock (the
"Warrants"), (5) depositary shares of the Company representing a fractional
interest in a share of Preferred Stock ("Depositary Shares"), or (6) stock
purchase contracts ("Stock Purchase Contracts") and stock purchase units ("Stock
Purchase Units") of the Company. The Debt Securities, Preferred Stock, Common
Stock, Warrants, Depositary Shares, Stock Purchase Contracts and Stock Purchase
Units are collectively referred to herein as the "Securities." The terms used
herein, unless otherwise defined, have the meanings assigned to them in the
Registration Statement.

     We have examined originals, photocopies or conformed copies of all such
records of the Company and its subsidiaries, all such agreements and
certificates of public officials, and such other documents as we have deemed
relevant and necessary as a basis for the opinion hereinafter expressed,
including without limitation:

     (1) the Company's bylaws and certificate of incorporation, each as amended
to the date hereof (the "Charter Documents");

     (2) the indenture for senior debt securities to be entered into between the
Company and the trustee, in the form included as an exhibit to Registration
Statement No. 333-83186 (the

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Danaher Corporation
May 2, 2003
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"Senior Indenture"), which was duly qualified under the Trust Indenture Act of
1939, as amended, upon effectiveness of Registration Statement No. 333-83186;
and

     (3) the indenture for subordinated debt securities to be entered into
between the Company and the trustee, in the form included as an exhibit to
Registration Statement No. 333-83186 (the "Subordinated Indenture"), which was
duly qualified under the Trust Indenture Act of 1939, as amended, upon
effectiveness of Registration Statement No. 333-83186.

As to any facts material to our opinion, we have made no independent
investigation of such facts and have relied, to the extent that we deem such
reliance proper, upon certificates of public officials and officers or other
representatives of the Company.

     In rendering the opinions set forth below, we have assumed that (i) all
signatures on all documents examined by us are genuine; (ii) all documents
submitted to us as originals are authentic and all documents submitted to us as
copies conform to the originals of those documents; (iii) each natural person
signing any document reviewed by us had the legal capacity to do so; (iv) each
person signing in a representative capacity (other than on behalf of the
Company) any document reviewed by us had authority to sign in such capacity; (v)
a Prospectus Supplement will have been prepared and filed with the Commission
describing the Securities offered thereby; (vi) all Securities will be issued
and sold in compliance with applicable federal and state securities laws and in
the manner stated in the Registration Statement and the applicable Prospectus
Supplement; (vii) the Senior Indenture and the Subordinated Indenture, together
with any supplemental indenture relating to a series of Debt Securities to be
issued under either of such indentures, will each be duly authorized, executed
and delivered by the parties thereto in substantially the form reviewed by us;
(viii) a definitive purchase, underwriting or similar agreement with respect to
any Securities offered will have been duly authorized and validly executed and
delivered by the Company and the other parties thereto; (ix) any Securities
issuable upon conversion, exchange or exercise of any Security being offered
will have been duly authorized, created and, if appropriate, reserved for
issuance upon such conversion, exchange or exercise; and (x) with respect to
shares of Common Stock or Preferred Stock offered, there will be sufficient
shares of Common Stock or Preferred Stock authorized under the Company's Charter
Documents and not otherwise reserved for issuance.

Based upon and subject to the foregoing, we are of the opinion that:

1. With respect to Debt Securities, when (i) the Company's Board of Directors
(the "Board") has taken all necessary corporate action to approve the issuance
and terms of the Debt Securities, the terms of the offering thereof and related
matters; (ii) the terms of the Debt Securities and of their issuance and sale
have been established so as not to violate any applicable law or result in a
default under or breach of any agreement or instrument binding upon the Company
and so as to comply with any requirement or restriction imposed by any court or
governmental body having jurisdiction over the Company; and (iii) the Debt
Securities have been duly executed, authenticated, issued and delivered in
accordance with the provisions of the Senior Indenture or the Subordinated
Indenture, as the case may be, and in accordance with the applicable definitive
purchase, underwriting or similar agreement approved by the Board upon

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Danaher Corporation
May 2, 2003
Page 3

payment of the consideration therefor provided for therein, the Debt Securities
will be legally issued and will constitute valid and binding obligations of the
Company, enforceable against the Company in accordance with their terms.

2. With respect to shares of Common Stock, when (i) the Board has taken all
necessary corporate action to approve the issuance and terms of the offering
thereof and related matters; and (ii) certificates representing the shares of
Common Stock have been duly executed, countersigned, registered and delivered
either (a) in accordance with the applicable definitive purchase, underwriting
or similar agreement approved by the Board upon payment of the consideration
therefor (not less than the par value of the Common Stock) provided for therein,
or (b) upon conversion, exchange or exercise of any other Security in accordance
with the terms of the Security or the instrument governing the Security
providing for the conversion, exchange or exercise as approved by the Board, for
the consideration approved by the Board (not less than the par value of the
Common Stock), the shares of Common Stock will be legally issued, fully paid and
non-assessable.

3. With respect to shares of any series of Preferred Stock, when (i) the Board
has taken all necessary corporate action to approve the issuance and terms of
the shares of the series, the terms of the offering thereof and related matters,
including the adoption of a resolution establishing and designating the series
and fixing and determining the preferences, limitations, and relative rights
thereof and the filing of a statement with respect to the series with the
Secretary of State of the State of Delaware as required under Section 151 of the
Delaware General Corporation Law (the "Certificate of Designation"); and (ii)
certificates representing the shares of the series of Preferred Stock have been
duly executed, countersigned, registered and delivered either (a) in accordance
with the applicable definitive purchase, underwriting or similar agreement
approved by the Board upon payment of the consideration therefor (not less than
the par value, if any, of the Preferred Stock) provided for therein, or (b) upon
conversion, exchange or exercise of any other Security in accordance with the
terms of the Security or the instrument governing the Security providing for the
conversion, exchange or exercise as approved by the Board, for the consideration
approved by the Board (not less than the par value, if any, of the Preferred
Stock), the shares of the series of Preferred Stock will be legally issued,
fully paid and non-assessable.

4. With respect to Depositary Shares, when (i) the Board has taken all necessary
corporate action to approve the issuance and terms of the Depositary Shares, the
terms of the offering thereof and related matters, including the adoption of a
Certificate of Designation relating to the Preferred Stock underlying the
Depositary Shares and the filing of the Certificate of Designation with the
Secretary of State of the State of Delaware; (ii) the depositary agreement or
agreements relating to the Depositary Shares (the "Depositary Agreements") have
been duly authorized and validly executed and delivered by the Company and the
depositary appointed by the Company; (iii) the shares of Preferred Stock
underlying the Depositary Shares have been deposited with a bank or trust
company (which meets the requirements for the depositary set forth in the
Registration Statement or any applicable Prospectus Supplement) under the
applicable Depositary Agreements; and (iv) the depositary receipts representing
the Depositary Shares have been duly executed, countersigned, registered and
delivered in accordance with the appropriate Depositary Agreement approved by
the Board upon payment of the consideration therefor

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Danaher Corporation
May 2, 2003
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provided for therein, the Depositary Shares will be legally issued and the
Depositary Agreements will constitute valid and binding obligations of the
Company, enforceable against the Company in accordance with their terms.

5. With respect to the Warrants, when (i) the Board has taken all necessary
corporate action to approve the creation of and the issuance and terms of the
Warrants, the terms of the offering thereof and related matters; (ii) the
warrant agreement or agreements relating to the Warrants have been duly
authorized and validly executed and delivered by the Company and the warrant
agent appointed by the Company; and (iii) the Warrants or certificates
representing the Warrants have been duly executed, countersigned, registered and
delivered, and authenticated by the warrant agent, in accordance with the
appropriate warrant agreement or agreements and the applicable definitive
purchase, underwriting or similar agreement approved by the Board upon payment
of the consideration provided for therein, the Warrants will be legally issued
and constitute valid and binding obligations of the Company, enforceable against
the Company in accordance with their terms.

6. With respect to Stock Purchase Contracts, when (i) the purchase agreement for
the Stock Purchase Contracts has been duly authorized and validly executed by
the parties thereto; (ii) the Board has taken all necessary corporate action to
approve and establish the terms of the Stock Purchase Contracts and to authorize
and approve the issuance thereof, the terms of the offering and related matters;
and (iii) the Stock Purchase Contracts have been duly executed and delivered in
accordance with the purchase agreement and the applicable definitive purchase,
underwriting or similar agreement approved by or on behalf of the Board upon
payment of the consideration therefor provided for therein, the Stock Purchase
Contracts will constitute valid and binding obligations of the Company,
enforceable against the Company in accordance with their terms.

7. With respect to Stock Purchase Units, when (i) the purchase agreement for the
Stock Purchase Units has been duly authorized and validly executed by the
parties thereto, (ii) the Board has taken all necessary corporate action to
approve and establish the terms of the Stock Purchase Units and to authorize and
approve the issuance thereof, the terms of the offering and related matters; and
(iii) the Stock Purchase Units have been duly executed and delivered in
accordance with the purchase agreement and the applicable definitive purchase,
underwriting or similar agreement approved by or on behalf of the Board upon
payment of the consideration therefor provided for therein, the Stock Purchase
Units will be legally issued.

     The foregoing opinions are qualified to the extent that the enforceability
of any document, instrument or Security may be limited by or subject to (i)
bankruptcy, insolvency, fraudulent transfer or conveyance, reorganization,
moratorium or other similar laws relating to or affecting creditors' rights
generally, and general equitable or public policy principles, and (ii) with
respect to any Debt Securities denominated in a currency other than United
States dollars, the requirement that a claim (or a foreign currency judgment in
respect of such a claim) with respect to such Securities be converted to United
States dollars at a rate of exchange prevailing on a date determined pursuant to
applicable law or governmental authority.

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Danaher Corporation
May 2, 2003
Page 5

     We express no opinions concerning (i) the validity or enforceability of any
provisions contained in the Senior Indenture or the Subordinated Indenture that
purport to waive or not give effect to rights to notices, defenses, subrogation
or other rights or benefits that cannot be effectively waived under applicable
law or (ii) the enforceability of indemnification provisions to the extent they
purport to relate to liabilities resulting from or based upon negligence or any
violation of federal or state securities or blue sky laws.

         We hereby consent to the filing of this opinion as an exhibit to the
Registration Statement, to the incorporation by reference of this opinion and
our consent to the filing of this opinion in any abbreviated registration
statement filed in connection with the Registration Statement pursuant to Rule
462(b) promulgated under the Securities Act, and to the statements made with
respect to us under the caption "Legal Matters" in the Prospectus included as
part of the Registration Statement.

         In rendering the foregoing opinion, we do not express an opinion
concerning any laws other than the laws of the State of New York, the general
corporate law of the state of Delaware and the federal laws of the United States
of America.

                                                   Sincerely,

                                                   WILMER, CUTLER & PICKERING


                                                By: /s/ Meredith B. Cross
                                                   -----------------------
                                                   Meredith B. Cross, a Partner

