Exhibit 99.1

Certain U.S. Federal Income Tax Consequences

The following discussion is a summary of certain U.S. federal income tax consequences relevant to the purchase, ownership and disposition of the senior unsecured debt securities (“notes”) of Kilroy Realty, L.P. but does not purport to be a complete analysis of all potential tax effects. The discussion is based upon the Internal Revenue Code of 1986, as amended (the “Code”), current, temporary and proposed U.S. Treasury Regulations issued thereunder (the “Treasury Regulations”), the legislative history of the Code, Internal Revenue Service (“IRS”) rulings, pronouncements, interpretations and practices, and judicial decisions now in effect, all of which are subject to change at any time. Any such change may be applied retroactively in a manner that could adversely affect a holder of the notes. This discussion does not address all of the U.S. federal income tax consequences that may be relevant to a holder in light of such holder’s particular circumstances. For example, except to the extent discussed in “—Non-U.S. Holders,” special rules not discussed here may apply to you if you are:

In addition, this discussion is limited to persons that purchase the notes in their initial offering to investors for cash at their “issue price,” within the meaning of Section 1273 of the Code (i.e., the first price at which a substantial amount of the notes is sold to purchasers other than bond houses, brokers or similar persons or organizations acting in the capacity of underwriters, placement agents or wholesalers) and that hold the notes as “capital assets,” within the meaning of Section 1221 of the Code (generally, property held for investment). This discussion does not address the effect of any applicable state, local, non-U.S. or other tax laws, including gift and estate tax laws.

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As used herein, “U.S. Holder” means a beneficial owner of the notes that is, for U.S. federal income tax purposes:

If any entity treated as a partnership for U.S. federal income tax purposes holds notes, the tax treatment of a partner in such partnership generally will depend upon the status of the partner and the activities of the partnership. If you are a partner of a partnership holding the notes, you should consult your tax advisor regarding the tax consequences of the purchase, ownership and disposition of the notes.

We have not sought and will not seek any rulings from the IRS with respect to the matters discussed below. There can be no assurance that the IRS will not take a different position concerning the tax consequences of the purchase, ownership or disposition of the notes or that any such position would not be sustained.

THIS SUMMARY OF CERTAIN U.S. FEDERAL INCOME TAX CONSEQUENCES IS FOR GENERAL INFORMATION ONLY AND IS NOT TAX ADVICE. PROSPECTIVE INVESTORS SHOULD CONSULT THEIR TAX ADVISORS REGARDING THE APPLICATION OF THE TAX CONSEQUENCES DISCUSSED BELOW TO THEIR PARTICULAR SITUATIONS, POTENTIAL CHANGES IN APPLICABLE TAX LAWS AND THE APPLICATION OF ANY STATE, LOCAL, FOREIGN OR OTHER TAX LAWS, INCLUDING GIFT AND ESTATE TAX LAWS, AND ANY TAX TREATIES.

U.S. Holders

Interest

A U.S. Holder generally will be required to recognize and include in gross income any stated interest as ordinary income at the time it is paid or accrued on the notes in accordance with such holder’s method of accounting for U.S. federal income tax purposes.

Sale or Other Taxable Disposition of the Notes

A U.S. Holder will recognize gain or loss on the sale, exchange, redemption (including a partial redemption), retirement or other taxable disposition of a note equal to the difference between the sum of the cash and the fair market value of any property received in exchange therefor (less a portion allocable to any accrued and unpaid stated interest, which generally will be taxable as ordinary income if not previously included in such holder’s income) and the U.S. Holder’s adjusted tax basis in the note. A U.S. Holder’s adjusted tax basis in a note (or a

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portion thereof) generally will be the U.S. Holder’s cost therefor, decreased by any payment on the note other than a payment of interest. This gain or loss will generally constitute capital gain or loss. In the case of a non-corporate U.S. Holder, including an individual, if the note has been held for more than one year, such capital gain will be subject to tax at a maximum tax rate of 15%, which maximum tax rate currently is scheduled to increase to 20% for dispositions occurring during taxable years beginning on or after January 1, 2011. The deductibility of capital losses is subject to certain limitations.

Information Reporting and Backup Withholding

A U.S. Holder may be subject to information reporting and backup withholding when such holder receives interest and principal payments on the notes or proceeds upon the sale or other disposition of such notes (including a redemption or retirement of the notes). Certain holders (including, among others, certain tax-exempt organizations) generally are not subject to information reporting or backup withholding. A U.S. Holder will be subject to backup withholding if such holder is not otherwise exempt and:

A U.S. Holder should consult its tax advisor regarding its qualification for an exemption from backup withholding and the procedures for obtaining such an exemption, if applicable. Backup withholding is not an additional tax. Any amounts withheld under the backup withholding rules from a payment to a U.S. Holder will be allowed as a credit against the holder’s U.S. federal income tax liability or may be refunded, provided the required information is furnished in a timely manner to the IRS.

Non-U.S. Holders

For purposes of this discussion, “Non-U.S. Holder” means a beneficial owner of the notes that is not a “U.S. Holder.” Special rules may apply to holders that are partnerships or entities treated as partnerships for U.S. federal income tax purposes and to Non-U.S. Holders that are subject to special treatment under the Code, including controlled foreign corporations, passive foreign investment companies, certain U.S. expatriates, and foreign persons eligible for benefits under an applicable income tax treaty with the United States. Such Non-U.S. Holders should consult their tax advisors to determine the U.S. federal, state, local and other tax consequences that may be relevant to them.

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Interest

Interest paid to a Non-U.S. Holder on its notes that is not effectively connected with the Non-U.S. Holder’s conduct of a U.S. trade or business will not be subject to U.S. federal withholding tax provided that:

A Non-U.S. Holder generally will also be exempt from withholding tax on interest if such amount is effectively connected with such holder’s conduct of a U.S. trade or business (and, if an income tax treaty applies, is attributable to a U.S. “permanent establishment”) (as discussed in “—Non-U.S. Holders—U.S. Trade or Business”) and the holder provides us or our paying agent with a properly executed IRS Form W-8ECI (or applicable successor form).

If a Non-U.S. Holder does not satisfy the requirements above, interest paid to such Non-U.S. Holder generally will be subject to a 30% U.S. federal withholding tax. Such rate may be reduced or eliminated under a tax treaty between the United States and the Non-U.S. Holder’s country of residence. To claim a reduction or exemption under a tax treaty, a Non-U.S. Holder must generally complete an IRS Form W-8BEN (or applicable successor form) and claim the reduction or exemption on the form.

Sale or Other Taxable Disposition of the Notes

A Non-U.S. Holder generally will not be subject to U.S. federal income tax or withholding tax on gain recognized on the sale, exchange, redemption, retirement or other disposition of a note so long as (i) the gain is not effectively connected with the conduct by the Non-U.S. Holder of a trade or business within the United States (or, if a tax treaty applies, the gain is not attributable to a U.S. permanent establishment maintained by such Non-U.S. Holder) and (ii) in the case of a Non-U.S. Holder who is an individual, such Non-U.S. Holder is not present in the United States for 183 days or more in the taxable year of disposition or certain other requirements are not met. Any amounts received in respect of accrued and unpaid interest will generally be treated as described in “—Non-U.S. Holders—Interest.” A Non-U.S. Holder who is an individual and does not meet an exemption should consult his or her tax advisor regarding the potential liability for U.S. federal income tax on such holder’s gain realized on a note.

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U.S. Trade or Business

If interest paid on a note or gain from a disposition of a note is effectively connected with a Non-U.S. Holder’s conduct of a U.S. trade or business (and, if an income tax treaty applies, the Non-U.S. Holder maintains a U.S. permanent establishment to which such amounts are generally attributable), the Non-U.S. Holder generally will be subject to U.S. federal income tax on the interest or gain on a net basis in the same manner as if it were a U.S. Holder. If a Non-U.S. Holder is subject to U.S. federal income tax on the interest on a net basis, the 30% withholding tax described above will not apply (assuming an appropriate certification is provided, generally on IRS Form W-8ECI). A Non-U.S. Holder that is a non-U.S. corporation may be subject to a branch profits tax equal to 30% of its effectively connected earnings and profits for the taxable year, subject to certain adjustments, unless it qualifies for a lower rate under an applicable income tax treaty. For this purpose, interest on a note or gain from a disposition of a note will be included in effectively connected earnings and profits if the interest or gain is effectively connected with the conduct by the foreign corporation of a trade or business in the United States.

Backup Withholding and Information Reporting

Backup withholding generally will not apply to payments of principal or interest made by us or our paying agents, in their capacities as such, to a Non-U.S. Holder of a note if the holder certifies as to its non-U.S. status in the manner described in “—Non-U.S. Holders—Interest.” However, information reporting generally will still apply with respect to payments of interest.

Payments of the proceeds from a disposition by a Non-U.S. Holder of a note made to or through a foreign office of a broker will not be subject to information reporting or backup withholding, except that information reporting (but generally not backup withholding) may apply to those payments, if the broker has certain enumerated connections with the U.S., provided, however, that such information reporting will not apply if the broker has documentary evidence in its records that the Non-U.S. Holder is a non-U.S. person and certain other conditions are met, or the Non-U.S. Holder otherwise establishes an exemption from information reporting.

Payment of the proceeds from a disposition by a Non-U.S. Holder of a note made to or through the U.S. office of a broker generally is subject to information reporting and backup withholding unless the holder or beneficial owner certifies as to its non-U.S. status in the manner described in “—Non-U.S. Holders—Interest” or otherwise establishes an exemption from information reporting and backup withholding.

A Non-U.S. Holder should consult its tax advisor regarding application of withholding and backup withholding in its particular circumstance and the availability of and procedure for obtaining an exemption from withholding and backup withholding under current Treasury Regulations. In this regard, the current Treasury Regulations provide that a certification may not be relied on if we or our agent (or other party) knows or has reason to know that the certification may be false. Any amounts withheld under the backup withholding rules from a payment to a Non-U.S. Holder will be allowed as a credit against the holder’s U.S. federal income tax liability or may be refunded, provided the required information is furnished in a timely manner to the IRS.

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