SecProbe.io

UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
WASHINGTON, D.C. 20549-7010

       DIVISION OF
CORPORATION FINANCE

Mail Stop 7010

July 2, 2008

via U.S. mail and facsimile

Mr. Robert G. Simpson    Senior Vice President and Chief Financial Officer
Waste Management, Inc.
1001 Fannin Street, Suite 4000
Houston, TX  77002
RE: Waste Management, Inc.
Form 10-K for the Year Ended December 31, 2007
  Filed February 19, 2008
Definitive Proxy Statement on Schedule 14A
  Filed March 26, 2008   File No. 001-12154

Dear Mr. Simpson:    We have reviewed these filings a nd have the following comments.  If you
disagree with a comment, we will consider your explanation as to why our comment is
inapplicable or a revision is unnecessary.  Pl ease be as detailed as necessary in your
explanation.  In some of our comments, we may ask you to provide us with supplemental information so we may better understand your  disclosure.  After reviewing this
information, we may or may not raise additional comments.

 Please understand that the purpose of our re view process is to assist you in your
compliance with the applicable disclosure requirements and to enhance the overall disclosure in your filings.  We look forward to working with you in these respects.  We
welcome any questions you may have about our comments or on any other aspect of our review.  Feel free to call us at the telephone numbers listed at the end of this letter.

Form 10-K for the Year Ended December 31, 2007

Risk Factors, page 12

1. In future filings, please delete the last  two sentences in the final paragraph on
page 12.  All material risks should be described.  If risks are not deemed material,
you should not reference them.

Mr. Robert G. Simpson
Waste Management, Inc.
July 2, 2008 Page 2  Legal Proceedings, page 18

2. We note your cross-reference to Note 10 of your Financial Statements for a
discussion of your legal proceedings.  If  you continue this practice in future
filings, please provide all information re quired by Item 103 of Regulation S-K for
all legal proceedings, including proceedi ngs with governmental authorities.
 Item 7. Management’s Discussion and Analys is of Financial Condition and Results of
Operations

Overview, page 23

3. We note you have presented free cash flow  disclosures on page 24.  In future
filings, please expand your disc losure to include all of the material limitations of
this measure, including, but not limite d to your ability to repay your debt
obligations.  To find out more about this , you can refer to Question 13 of our June
13, 2003 FAQ’s on Non-GAAP Financial Measures.

Critical Accounting Estimates and Assumptions, page 25
 Accounting for Landfills

4. We note that accounting for landfills and re lated costs is a critical accounting
estimate and involves many complicated assumptions. Those include the permitted and future capacity and future investments. Because of the judgment and complexity of this issue, we ur ge you to consider providing additional
information and analysis.  This information should be quantified and presented in tabular formats to assist in understanding.  This information would be best
included with your landfill capacity info rmation shown on page 5. It would
appear appropriate to include this info rmation in either MD&A, or a footnote.
Specifically we request that in futu re filings you provide the following:

- An analysis of your investment in landfills, showing non-depletable land,
development costs, constructi on-in-progress and accumulated
depletion/amortization;
- An estimate of future costs to be incurred on permitted and expanded landfills;
- Show a calculation of your average per ton rates for each period presented;
- Provide narrative analysis explaining significant changes in estimates of
future costs, and changes in estimates of landfill capacity. Such narratives should be accompanied by quantified imp acts that such changes in estimates
have had on the results of operations.

It appears that you may use different per t on rates for each landf ill. If so, we still
urge you to consider ways in which you can  quantify the impact of changes in the

Mr. Robert G. Simpson
Waste Management, Inc.
July 2, 2008 Page 3
assumptions described above.  In other word s, isolate the impact  that the change
in estimate of future costs had on th e results of operations, independent of
acquisitions and divestitures. Quantify the impact that the net change in estimated landfill capacity had on results of operati ons independent of acquisitions and
divestitures. Explain why the estimates changed.
 Controls and Procedures, page 116

5. You only refer to one aspect of disclosure controls and procedures and omit the
reference to accumulation and communication to management of information.  If
true, please confirm supplementally that based upon the evaluation your
management, including your CEO and CFO, you also concluded that as of December 31, 2007 your disclosure controls  and procedures were effective to
ensure that information required to  be disclosed is accumulated and
communicated to management as appropriate  to allow timely decisions regarding
required disclosure.  Please include this disclosure in future filings.

Definitive Proxy Statement on Schedule 14A
 Executive Compensation, page 13

6. In future filings, please explain what “i ndividual performance modifier” means.
In addition, please clarify whether the adjustments can go up or down.

7. We note your table on page 17 relating to  the annual bonuses for named executive
officers.  In future filings, please disclose how the actual results achieved are correlated to the percentage of payout earned.

8. On page 20, you discuss the fact that so me or all of the payout under the 2005
awards made to “covered employees” may not be deductible for federal income
tax purposes.  In future filings, please c onsider providing quantification so that
investors can better understand what this means.

Performance Share Units, page 20

9. We note your disclosure in the last paragraph of this section that your exclusion of
extraordinary, unusual, and one-time items from calculating performance payouts
is consistent with your compensation ph ilosophy.  Please tell  us, with a view
toward future disclosure, which compone nt(s) of your philosophy to which this
statement refers.

Mr. Robert G. Simpson
Waste Management, Inc.
July 2, 2008 Page 4  Summary Compensation Table, page 20

10. Please provide the information requested  by Item 407(e)(4) of Regulation S-K
under the caption “Compensation Co mmittee Interlocks and Insider
Participation.”

*    *    *    *
      Please respond to these comments with in 10 business days, or tell us when you
will provide us with a response.  Please pr ovide us with a supplemental response letter
that keys your responses to our comment s and provides any requested supplemental
information.  Detailed letters greatly facilitate our review.  Please furnish your supplemental response on EDGAR as a corres pondence file.  Pleas e understand that we
may have additional comments after reviewing your responses to our comments.
We urge all persons who are responsible for the accuracy and adequacy of the
disclosure in the filings reviewed by the staff to be certain that they have provided all information investors require for an info rmed decision.  Since the company and its
management are in possession of all facts re lating to a company’s disclosure, they are
responsible for the accuracy and adequacy of the disclosures they have made.
  In connection with responding to our comments, please provide, in writing, a statement from the company acknowledging that:
• the company is responsible for the adequacy  and accuracy of the disclosure in the
filing;

• staff comments or changes to disclosure  in response to staff comments do not
foreclose the Commission from taking any action with respect to the filing; and

• the company may not assert staff comme nts as a defense in any proceeding
initiated by the Commission or any person under the federal secu rities laws of the
United States.
   In addition, please be advi sed that the Division of En forcement has access to all
information you provide to the staff of the Divi sion of Corporation Fi nance in our review
of your filing or in response to our comments on your filing.

Mr. Robert G. Simpson
Waste Management, Inc.              July 2, 2008 Page 5
You may contact Jessica Ka ne, Staff Attorney, at (202) 551-3235 or, in her
absence, to Lesli Sheppard, Staff Attorne y, at (202) 551-3708, if you have any questions
regarding legal or disclosure matters.  Pl ease contact Ryan Rohn, Staff Accountant, at
(202) 551-3739 or, in his absence, to the undersigned at (202) 551-3689 if you have questions regarding comments on the financ ial statements and related matters.
        S i n c e r e l y ,            John Hartz        Senior Assistant Chief Accountant