Mail Stop 4-6

      April 4, 2005

Stephen Green
Senior Vice President and General Counsel
IHS, Inc.
15 Inverness Way East
Englewood, CO  80112

Re:  	IHS, Inc.
	Amendment No. 1 to Form S-1
		Filed March 18, 2005
	File No. 333-122565

Dear Mr. Green:

We have reviewed your amended Form S-1 and have the following
comments.

General
1. You disclose in Exhibit A to your March 18, 2005, response
letter
that your government customers include National Oil Company Libya.
You disclose in Exhibit B that the countries in which your
customers
are located include Libya, Sudan, and Syria.  In light of the fact
that Libya, Sudan and Iran have been identified by the U.S. State
Department as state sponsors of terrorism, and Sudan and Iran are
subject to economic sanctions administered by the U.S. Treasury
Department`s Office of Foreign Assets Control, and Libya was
subject
to economic sanctions until September 21, 2004, please summarize
for
us the Company`s operations in each of these countries, and
describe
for us the materiality to the Company of its operations in each
country and your view as to whether those operations,
individually,
or in the aggregate, constitute a material investment risk for
your
security holders.  In preparing your response, please consider
that
evaluations of materiality should not be based solely on
quantitative
factors, but should include consideration of all factors,
including
the potential impact of corporate activities upon a company`s
reputation and share value that a reasonable investor would deem
important in making an investment decision.
2. See prior comment 8.  Given your agreement not to disclose the
name of the customer identified in the summary as "one of the
world`s
largest aerospace companies," we do not believe that this example
is
appropriate.  As you know, the summary should be limited to key
aspects of the offering, which would not ordinarily include an
unnamed large customer.  Please choose an appropriate example or
revise to eliminate this reference.

Summary Consolidated Financial Data, page 6

Non-GAAP Measures - EBITDA
3. We have reviewed your response to prior comment no. 10 and your
revisions on pages 9 and 10 and it continue to appear that your
presentation does not adequately comply with the requirements of
Item
10(e) of Regulation S-K and the guidance set forth in the
Frequently
Asked Questions Regarding the Use of Non-GAAP Financial Measures.
In
this regard, please note the following and advise and revise your
disclosures containing non-GAAP information as necessary.
o Note that EBITDA and Adjusted EBITDA, used as measures of
performance, represent non-GAAP measures.  Accordingly, all
comments
and disclosures items relate to both measures.  Refer to Question
15,
Frequently Asked Questions Regarding the Use of Non-GAAP Financial
Measures.
o We still do not believe you have overcome the burden of
demonstrating the usefulness of EBITDA and Adjusted EBITDA as a
performance measure.  Because your non-GAAP measures exclude
recurring charges, further demonstrate the usefulness of these
measures that exclude recurring items to evaluate performance.
o Where you discuss (i) non-cash items included in the
reconciliation
from EBITDA to adjusted EBITDA, you state that `management
believes
that investors can better assess operating performance if the
measures are presented without such items.`  However, you do not
explain the basis for this belief. Please advise.  Ensure you
fully
address why you believe it is useful to investors to eliminate
non-
cash items, where you are assessing ongoing operating performance.
o Where you discuss (ii) items that you do not consider to be
relevant to assessing operating performance, further disclose the
specific adjustments that have no continuing relevance to your
ongoing business. Supplementally describe to us and disclose
management`s criteria for determining such items are "relevant"
when
assessing its operating performance.
o You indicate that EBITDA and adjusted EBITDA are useful to
investors because they are frequently used by securities analysts,
lenders and other interested parties to evaluate your peer
companies.
However, the manner in which others use this measure does not
provide
insight as to its usefulness to you or your investors.
Supplementally describe the manner in which management uses the
measures to conduct or evaluate its business.  Include the
economic
substance behind management`s decision to use such measure.
Management should identify significant factors that should be
considered, and discuss significant trends or requirements not
captured by the measurements to ensure balance and avoid undue
reliance on the measure.  In addition, tell us and disclose how
these
measures can be used to evaluate IHS against its peer companies in
light of your disclosure that not all companies use identical
calculations and therefore these measures may not be comparable.
o If you are able to overcome the burden of demonstrating the
usefulness of your non-GAAP measures, revise to include all of the
disclosures identified in Question 8, Frequently Asked Questions
Regarding the Use of Non-GAAP Financial Measures.

4. See prior comments 12 and 73.  It appears from your
supplemental
response and revised disclosure that you are substantially
dependent
on license agreements with some 25 SDOs.  Please provide more
fully
discuss these agreements and business and explain why these
license
agreements should not be filed as material contracts pursuant to
Item
601(b)(10) of Regulation S-K.
5. See prior comment 13.  We note the revised disclosure in risk
factors.  In business, please include an appropriately detailed
discussion regarding your dependence on contractors, the number of
contractors employed by segment, and the impact of such reliance
on
your business.
6. See prior comment 15.  We disagree that disclosure regarding
the
protection of non-affiliated shareholders is inappropriate.
Potential shareholders should be made aware of any measures the
company has taken to protect their interests.  If none have been
taken, this would be material information to shareholders.  As
appropriate, please revise to disclose the limited protections you
believe the company has afforded to non-affiliated shareholders.

Use of Proceeds
7. See prior comment 16.  We note your disclosure that you have no
current "agreements or commitments pending" to acquire additional
businesses.  Have you identified any prospective acquisition
candidates, made proposals to or entered into letters of intent,
whether binding or non-binding, with any acquisition candidates?
To
the extent that you have any current plans, proposals or
arrangements
to engage in acquisitions or otherwise have committed the proceeds
from this offering, such information should be disclosed.
8. See prior comment 17.  We note your supplemental response.  As
you
know, this section in not limited to a discussion of definitive
plans; it is appropriate to disclose preliminary plans and
intended
uses of any part of the proceeds and the order of priority of in
which the proceeds would be used.  Please provide the requested
disclosure.
9. We note further your reference in this section to investing in
"short-term, marketable securities." To the extent that you intend
to
invest in "investment grade" securities, please revise the
disclosure
accordingly.

Management`s Discussion and Analysis

Revenue Recognition, page 28
10. We note you response to our previous comment No. 21.  We note
that you have revised your revenue recognition policy descriptions
within the Critical Accounting Policies in MD&A to identify the
types
of assumptions that underlie the most significant and subjective
estimates.  In addition, within this section you should:

* Discuss the sensitivity of those estimates to deviation of
actual
results from your assumptions; and
* Describe circumstances that have resulted in revised assumptions
in
the past.

Revise your disclosures to provide meaningful insight into the
quality and variability of your critical accounting policies.  See
SEC Release No 33-8040 and FR-60.

Results in Operations
11. We note that you segregated revenues and cost of revenues by
products and services in response to prior comment 46 in your
summary
consolidated financial data in your summary and on your income
statement.  Please provide similar disclosure where revenues and
cost
of revenues are disclosed, for example, selected historical
consolidated financial data on page 22 and results of operations
on
page 31.
12. Revise your MD&A disclosure to provide information necessary
for
an investor to understand material changes in financial condition
and
known trends indicated by these changes.  Refer to Regulation S-K,
Item 303.  Examples include, but are not limited to, the
following:

* Increases in Accrued Royalties and Accrued Compensation; and
* Increases in Deferred Subscription Revenues.
13. See prior comment 23.  We do not understand your response that
your systems are not designed to capture the data requested.  To
the
extent that you experienced material increases in revenues, ensure
that you disclose the extent to which the increases were
attributable
to increases in prices or in the volume of products or services
sold.
See Item 303(a)(3)(iii) of Regulation S-K.

Business
14. See prior comment 31.  Your supplemental response and the
disclosure in the registration document do not appear to be
consistent.  Your supplemental response suggests that your plans
are
too preliminary to have completed an assessment of the risks
associated with operating in emerging market economies you
identified.  Yet you state on page 51 that you expect to add
locations in India this year and in the summary, intended for the
key
aspects of the offering, you discuss the significant opportunities
that the three countries represent for the company.  In this
light,
your revised risk factor disclosure, which includes a generic
reference to the "additional or more significant risks" associated
with expanding your operations in those countries, does not appear
to
be adequate.  If you have plans to begin operations in India this
year, a discussion of the added and possibly more significant
risks
is material information.  Please revise accordingly.
15. See prior comment 33.  Please tell us whether you are
significantly dependent on any of the 86 registered trademarks
and,
if so, discuss the importance of the trademarks to and the effect
on
each business segment.  See Item 101(c)(1)(iv) of Regulation S-K.
Please note that this disclosure requirement relates to licenses,
which you indicate are heavily relied upon.

Executive Compensation
16. We are unable to locate disclosure regarding the company`s
agreement to pay for the membership deposit and the monthly family
dues for the country club membership of the Picassos. See exhibit
10.21. Please advise or revise.

Shares Eligible for Future Sale
17. See prior comment 40.  We note your supplemental response.
Please disclose that the underwriters do not have any current
intent
or arrangement to release any of the shares subject to the lock-up
agreements prior to their expiration but that any release is at
the
sole discretion of Goldman Sachs and Citigroup.

Underwriting
18. See prior comment 41.  We note your supplemental response that
substantively similar materials for electronic distribution were
submitted to and approved by our Office of Chief Counsel.  Please
provide us with copies of the materials intended to be distributed
electronically by each of Citigroup and UBS Securities LLC.

Financial Statements

Report of Independent Registered Public Accounting Firm, page F-2

19. We note the revision to the report; however, we believe it
must
comply with the specific language in Interpretation 18 of AU
Section
9508.  Please revise.

Note 1.  Nature of Business and Significant Accounting Policies

Revenue Recognition, page F-7

Sales of Critical Information and Decision-Support Tools

20. We note you response to our previous comment No. 49.
Supplementally tell us whether you offer your dealers and/or users
any price protection or rights of return for non-subscription
based
products.  Refer to SFAS 48.

Services

21. We note you response to our previous comment No. 52 and your
revised disclosure that indicates services are provided on a
stand-
alone basis or as a part of a multiple element arrangement.  For
services that are provided as part of a multiple element
arrangement
where your services are not in a standard-price book, help us
understand how you determine VSOE of fair value for those
services.
In this regard, your response and disclosures indicate that for
services that are not in a standard-price book, as the price
varies
based on the nature and complexity of the service offering, value
is
derived based on the estimated underlying effort for executing the
associated deliverable in the contract.   Is your reference to
`value` intended to refer to VSOE of fair value?  If so, help us
understand why you believe this `value` represents VSOE of fair
value
under paragraph 10 of SOP 97-2, particularly where the service is
so
unique and complex, so that it is not stated in your price-book.
Further explain how you determine the `estimated underlying effort
for executing the associated deliverable in the contract`, and how
these estimates represent VSOE.  Please provide us supplementally
any
additional information surrounding these services to help us
understand your accounting under SOP 97-2.

22. Also, address why you believe it is appropriate to account
separately for the service elements where your services are unique
and complex.  Address whether these services require significant
production, modification or customization of the software or
whether
the services are essential to the functionality of the other
elements
of the arrangement.  Refer to paragraphs 7 and 65 of SOP 97-2.
Further address the criteria in paragraphs 70 and 71 of SOP 97-2
to
support your conclusion.

23. Refer to prior comment no. 52.  Your disclosure indicates that
revenue related to time-and-material-based contracts is recognized
in
the period performed at the rate specified in the contract.
Address
whether the rate specified in the contract represents VSOE.  If
so,
address the basis for your conclusion and revise to clarify.

24. Refer to prior comment no 53.  We have reviewed your response
and
revised disclosures surrounding your fixed price contracts and
understand that revenue is recognized for an element in the period
that the performance obligation is completed.  Explain the typical
duration of these service elements and clarify how you account for
the respective costs prior to recognition of the completed
services.

Multiple Element Arrangements

25. While your disclosures indicate your accounting where VSOE
does
and does not exist, your revised disclosures do not indicate how
you
determine VSOE for your critical information, decision-support
tools
and maintenance. In this regard, you refer to certain contracts
that
specify separate fees; however, this may not necessarily represent
VSOE of fair value. Please advise and revise as necessary.

26. Your revised disclosure provides your accounting in three
bullets
where VSOE exists.  Regarding the first bullet, you indicate that
revenue for each element is generally recognized upon delivery of
the
product or completion of the services or ratably over the term of
the
maintenance period.  Clarify how you determine when to recognize
the
revenue upon delivery or completion or over the maintenance
period.

27. Regarding the second bullet, you indicate that where customer
acceptance is required for services rendered, revenue is
recognized
in the period that customer acceptance is obtained.  Do you mean
that
you defer revenues associated with all of the elements in the
arrangement or only the amount allocated to services?  Revise to
clarify and refer to the literature that supports your accounting.

28. Regarding the third bullet, you indicate that for subscription
offerings of a multiple-element arrangement, you recognize revenue
ratably over the subscription period.  Does this accounting apply
for
all elements? Help us understand this accounting, particularly
where
you have VSOE for all elements in the arrangement.

29. For multiple element arrangements were VSOE is not available,
you
indicate that you recognize revenue after all obligations of
performance are completed.  Tell us how this complies with
paragraphs
12 of SOP 97-2.  Provide us an example where you did not have VSOE
for some or all of the elements in your arrangements. If you did
not
have VSOE for maintenance, would you wait to recognize all
revenues
under the arrangement at the end of the maintenance period?
Please
clarify.

Software Development Costs, page F-10

30. We note you response to our previous comment No. 54.
Supplementally clarify whether your software development costs
relate
to software that is sold, leased or otherwise marketed (SFAS 86)
or
whether they relate to software for internal use (SOP 98-1).  In
this
regard your reference to SFAS 86 and SOP 98-1 is confusing.  If
your
capitalized software costs relate to software that is sold, leased
or
otherwise marketed, supplementally explain how your amortization
policy complies with paragraph 8 of SFAS 86.

Stock Option Accounting, page F-11

31. Reconcile and explain the differences between the fair values
underlying shares of common stock of any new grants since your
last
disclosure to us and the midpoint of your offering range.  This
reconciliation should describe significant intervening events
within
the company and changes in assumptions within the valuation
methodologies employed that explain the changes in fair value of
your
common stock up to the filing of the registration statement.
Continue to provide us with updates to the above analysis for all
equity-related transactions through the effectiveness date of the
registration statement.

32. We note you response to our previous comment No. 56.
Supplementally include in your financial statements the following
disclosure for equity instruments granted in the last 12 months
prior
to the date of the most recent balance sheet included in the
registration statement. The information you provide should address
the options previously granted at the subsidiary level and the
restricted stock and deferred stock units you recently granted:

* For each grant date, the number of options or shares granted,
the
exercise price, the fair value of common stock, and the intrinsic
value, if any per option (the number of options may be aggregated
by
month or quarter and the information presented as weighted average
per-share amounts;
* Whether the valuation used to determine the fair value was
contemporaneous or retrospective;
* If the valuation specialist was a related party, a statement
indicating that fact.

33. Also, expand your MD&A to include the following information
related to issuances of equity instruments:
* A discussion of the significant factors, assumptions, and
methodologies used in determining fair value;
* A discussion of each significant factor contributing to the
difference between the fair value as of each date of grant and the
estimated IPO price; and
* The valuation alternative selected and the reason management
chose
not to obtain a contemporaneous valuation by an unrelated
valuation
specialist.

34. Tell us supplementally and revise to clarify the manner in
which
you selected what you deemed to be the `most representative`
indicator of fair market value where you established $9 and $9.42
per
share to represent the fair value at the respective dates.
Quantify
the range of values determined by the methodologies you employed
and
clarify how you derived the respective fair values.  Also, explain
to
us the underlying reasons for the differences between the fair
value
of your subsidiary common stock ($9.42) and the fair value of your
common stock ($9.12) in November 2004.

Note 14. Employee Retirement Benefits, page F-25

35. We note your response to prior comment 14.  We have the
following
additional comments:
* Tell us the name of the sponsor of the TBG Retirement Income
Plan
post spin-off.  Is the sponsor part of the IHS Inc. consolidated
group?
* Tell us the name of the sponsor of the new IHS Retirement Income
Plan and the relation of the entity to IHS Inc.
* We note that you believe the spin-off is consistent with the
rules
contained in I.R.C Section 414(l)(1) and the relevant regulations.
Tell us more about the `other relevant` regulations and explain
the
formal process under these regulations.  Do the transfer of plan
assets and change of plan sponsor require formal notification from
DOL/ERISA?  If so, did you receive such notice?
* Tell us whether the employing units spun-off to create the IHS
Retirement Income Plan related solely to employing units that are
part of IHS Inc.`s operations and subsidiaries.  Do any of the
employing units remaining in the TBG Retirement Income Plan relate
to
IHS Inc.`s operations or subsidiaries?
* Tell us why TBG Services Inc. was the sponsor of the TBG
Retirement
Plan before the spin-off.
* We note your disclosure that prior to November 30, 2004 your
U.S.
plan was part of a multi-employer plan sponsored by your
consolidated
subsidiary.  Tell us the name of the participants in the multi-
employer plan.
* Tell us whether you considered accounting for the spin-off as a
curtailment or settlement under SFAS 88 and why you ultimately
concluded your accounting is appropriate.
* Tell us how the TBG Retirement Income Plan became significantly
overfunded.  Is it principally due to excess employer
contributions
or due to market factors?

Note 20.  Earnings per Common Share

36. Refer to our prior comment no. 59.  Supplementally explain why
you believe it is appropriate to aggregate both classes of common
stock in your earnings per share calculation with reference to the
appropriate authoritative literature.  In this regard, it appears
SFAS 128 and EITF 03-6 require the presentation of a basic and
diluted EPS for each class of common stock.  Please advise and
revise
as necessary.

37. Also, help us understand the basis for the weighted average
shares outstanding for the periods presented.  In this regard,
address whether the shares issued in the recapitalization in 2004
represent nominal issuances of common stock.  Explain why you have
not treated the recapitalization in a manner similar to a stock
split
or stock dividend for which retroactive treatment is required by
paragraph 54 of Statement 128.  Refer to SAB Topic 4D.
* * * * * * *

    As appropriate, please amend your registration statement in
response to these comments. You may wish to provide us with marked
copies of the amendment to expedite our review.  Please furnish a
cover letter with your amendment that keys your responses to our
comments and provides any requested supplemental information.
Detailed cover letters greatly facilitate our review.  We may have
additional comments based on reviewing your amendment and
responses
to our comments.

    You may contact Brent Watson at 202-824-5494 or Lisa
Mitrovich,
Assistant Chief Accountant, at 202-942-1836, if you have questions
regarding comments on the financial statements and related
matters.
Please address all other comments to Maryse Mills-Apenteng at
 202-942-1861.  If you require further assistance you may contact
the
undersigned at 202-942-1800.

								Sincerely,



								Barbara C. Jacobs
								Assistant Director

cc:	Via facsimile:  212-450-3596
      Luciana Fato, Esq.
      Davis Polk & Wardwell
      450 Lexington Avenue
      New York, NY  10017