**EXHIBIT 31.1**

 

**CERTIFICATION**

 

I,            Douglas C. Morrison, certify that:

 

| 1. | I have reviewed this annual report on Form 10-K, and all                            reports on Form 8-K containing distribution or servicing reports filed                            in respect of periods included in the year covered by this annual                            report, of Citibank Omni-S Master Trust; |
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| 2. | Based on my knowledge, the information in these reports,                            taken as a whole, does not contain any untrue statement of a material                            fact or omit to state a material fact necessary to make the statements                            made, in light of the circumstances under which such statements were                            made, not misleading as of the last day of the period covered by this                            annual report; |
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| 3. | Based on my knowledge, the distribution or servicing                            information required to be provided to the trustee by the servicer                            under the pooling and servicing, or similar, agreement for inclusion in                            these reports is included in these reports; |
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| 4. | Based on my knowledge and upon the annual compliance                            statement included in the annual report and required to be delivered to                            the trustee in accordance with the terms of the pooling and servicing,                            or similar, agreement, and except as disclosed in the reports, the                            servicer has fulfilled its obligations under that agreement;                            and |
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| 5. | The reports disclose all significant deficiencies                            relating to the servicer’s compliance with the minimum servicing                            standards based upon the report provided by an independent public                            accountant, after conducting a review in compliance with the Uniform                            Single Attestation Program for Mortgage Bankers or similar procedure,                            as set forth in the pooling and servicing, or similar, agreement, that                            is included in these reports. |
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Date:            March 26, 2008

 

 

| /s/ Douglas C. Morrison   |   |
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Douglas            C. Morrison

President

Citi            Omni-S Finance LLC

 

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