Exhibit 31

CERTIFICATION

I,
Paul S. Viviano, certify that:

1.     I
have reviewed this report on Form 10-Q of Alliance Imaging, Inc.;

2.     Based
on my knowledge, this report 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 with respect to the period covered by this report;

3.     Based
on my knowledge, the financial statements, and other financial information included in this report, fairly present in all material respects the financial condition,
results of operations and cash flows of the registrant as of, and for, the periods presented in this report;

4.     The
registrant's other certifying officer and I are responsible for establishing and maintaining disclosure controls and procedures (as defined in Exchange Act
Rules 13a-15(e) and 15d-15(e)) and internal control over financial reporting (as defined in Exchange Act Rules 13a-15(f) and 15d-15(f))
for the registrant and we have:



5.     The
registrant's other certifying officer and I have disclosed, based on our most recent evaluation of internal control over financial reporting, to the registrant's
auditors and the audit committee of the registrant's board of directors (or persons performing the equivalent functions):



|                        |  |                                                                                     
|----------------------- |  | ------------------------------------------------------------------------------------
|Dated: November 7, 2008 |  | /s/PAUL S. VIVIANO Paul S. Viviano Chairman of the Board and Chief Executive Officer

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CERTIFICATION

I,
Howard K. Aihara, certify that:

1.     I
have reviewed this report on Form 10-Q of Alliance Imaging, Inc.;

2.     Based
on my knowledge, this report 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 with respect to the period covered by this report;

3.     Based
on my knowledge, the financial statements, and other financial information included in this report, fairly present in all material respects the financial condition,
results of operations and cash flows of the registrant as of, and for, the periods presented in this report;

4.     The
registrant's other certifying officer and I are responsible for establishing and maintaining disclosure controls and procedures (as defined in Exchange Act
Rules 13a-15(e) and 15d-15(e)) and internal control over financial reporting (as defined in Exchange Act Rules 13a-15(f) and 15d-15(f))
for the registrant and we have:



5.     The
registrant's other certifying officer and I have disclosed, based on our most recent evaluation of internal control over financial reporting, to the registrant's
auditors and the audit committee of the registrant's board of directors (or persons performing the equivalent functions):



|                        |  |                                                                                          
|----------------------- |  | -----------------------------------------------------------------------------------------
|Dated: November 7, 2008 |  | /s/HOWARD K. AIHARA Howard K. Aihara Executive Vice President and Chief Financial Officer

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