IndyMac Residential Asset Securitization Trust 2007-A1

Mortgage Pass-Through Certificates

May 25, 2007 Distribution

External Parties

Table of Contents

Page

Seller

1. Certificate Payment Report

IndyMac Bank

2. Collection Account Report

3. Credit Enhancement Report

Servicer(s)

4. Collateral Report

IndyMac Bank

5. Delinquency Report

6. REO Report

Underwriter(s)

7. Foreclosure Report

HSBC Bank

8. Prepayment Report

Deutsche Bank Securities

9. Prepayment Detail Report

10. Realized Loss Report

Cap Provider

11. Realized Loss Detail Report

Bear Stearns Fin. Products.Inc

12. Triggers and Adj. Cert. Report

13. Other Related Information

Total Number of Pages

Dates

Contacts

Cut-Off Date:

January 01, 2007

Jennifer Hermansader

Close Date:

January 30, 2007

Administrator

First Distribution Date:

February 26, 2007

(714) 247-6258

Jennifer.Vandyne@db.com

Address:

Distribution Date:

May 25, 2007

1761 East St. Andrew Place, Santa Ana, CA 92705

Record Date:

April 30, 2007

Factor Information:

(800) 735-7777

May 24, 2007

Main Phone Number:

(714) 247-6000

Determination Date:

May 18, 2007

https://www.tss.db.com/invr

Page 1 of 26

IndyMac Residential Asset Securitization Trust 2007-A1



Mortgage Pass-Through Certificates
Mortgage Pass-Through Certificates
May 25, 2007 Distribution

Certificate Payment Report
Current Period Distribution -
			Prior						Current
			Prior

	Class	Original	Principal			Total	Realized	Deferred	Principal

Class	Type	Face Value	Balance	Interest	Principal	Distribution	Loss	Interest	Balance
			(1)	(2)	(3)	(4)=(2)+(3)	(5)	(6)	(7)=(1)-(3)-(5)+(6)
A-1	INT	60,864,674.00	60,864,674.00	304,323.37	0.00	304,323.37	0.00	0.00	60,864,674.00
A-1	INT	60,864,674.00	60,864,674.00	304,323.37	0.00	304,323.37	0.00	0.00	60,864,674.00
A-2	INT	14,162,721.00	14,162,721.00	70,813.61	0.00	70,813.61	0.00	0.00	14,162,721.00
A-3	INT	123,364,500.00	113,165,647.96	558,283.86	2,277,978.18	2,836,262.04	0.00	0.00	110,887,669.78
A-4	NTL	0.00	0.00	0.00	0.00	0.00	0.00	0.00	0.00
A-5	INT	21,181,500.00	19,430,372.37	92,618.11	391,125.45	483,743.56	0.00	0.00	19,039,246.92
A-6	NTL	0.00	0.00	28,109.93	0.00	28,109.93	0.00	0.00	0.00
A-7	INT	896,608.00	896,608.00	4,483.04	0.00	4,483.04	0.00	0.00	896,608.00
A-8	INT	72,273,000.00	69,020,715.61	345,103.58	1,084,094.79	1,429,198.37	0.00	0.00	67,936,620.82
A-9	INT	72,273,000.00	69,020,715.62	330,724.26	1,084,094.80	1,414,819.06	0.00	0.00	67,936,620.82
A-10	NTL	0.00	0.00	14,379.32	0.00	14,379.32	0.00	0.00	0.00
A-X	NTL	0.00	0.00	143,454.42	0.00	143,454.42	0.00	0.00	0.00
PO	INT	1,265,942.00	1,262,252.84	0.00	2,043.91	2,043.91	0.00	0.00	1,260,208.93
B-1	INT	7,732,000.00	7,720,726.78	38,603.63	3,778.47	42,382.10	0.00	0.00	7,716,948.31
B-2	INT	4,446,000.00	4,439,517.76	22,197.59	2,172.67	24,370.26	0.00	0.00	4,437,345.09
B-3	INT	2,319,000.00	2,315,618.91	11,578.09	1,133.25	12,711.34	0.00	0.00	2,314,485.66
B-4	INT	2,513,000.00	2,509,336.05	12,546.68	1,228.05	13,774.73	0.00	0.00	2,508,108.00
B-5	INT	1,933,000.00	1,930,181.69	9,650.91	944.62	10,595.53	0.00	0.00	1,929,237.07
B-6	INT	1,352,312.06	1,350,340.40	6,751.70	660.84	7,412.54	0.00	0.00	1,349,679.56
A-R	INT	100.00	0.00	0.00	0.00	0.00	0.00	0.00	0.00


Total		386,577,357.06	368,089,428.99	1,993,622.10	4,849,255.03	6,842,877.13	0.00	0.00	363,240,173.96
Total





Page 2 of 26

IndyMac Residential Asset Securitization Trust 2007-A1



Mortgage Pass-Through Certificates
Mortgage Pass-Through Certificates
May 25, 2007 Distribution


Interest Accrual Detail Current Period Factor Information per $1,000 of Original Face Value
					Orig. Principal	Prior				Current
					Orig. Principal	Prior				Current
	Period	Period			(with Notional)	Principal			Total	Principal
Class	Starting	Ending	Method	Cusip	Balance	Balance	Interest	Principal	Distribution	Balance
			Method
					(1)	(1)	(2)	(3)	(4)=(2)+(3)	(5)

A-1	04/01/07	04/30/07	A-30/360	761136AA8	60,864,674.00	1,000.000000	5.000000	0.000000	5.000000	1,000.000000
A-1	04/01/07	04/30/07	A-30/360	761136AA8	60,864,674.00	1,000.000000	5.000000	0.000000	5.000000	1,000.000000
A-2	04/01/07	04/30/07	A-30/360	761136AB6	14,162,721.00	1,000.000000	5.000000	0.000000	5.000000	1,000.000000
A-3	04/25/07	05/24/07	F-30/360	761136AC4	123,364,500.00	917.327497	4.525482	18.465427	22.990909	898.862070
A-4	04/25/07	05/24/07	F-30/360	761136AD2	123,364,500.00	917.327497	0.000000	0.000000	0.000000	898.862070
A-5	04/25/07	05/24/07	F-30/360	761136AE0	21,181,500.00	917.327497	4.372594	18.465427	22.838022	898.862069
A-6	04/25/07	05/24/07	F-30/360	761136AF7	21,181,500.00	917.327497	1.327098	0.000000	1.327098	898.862069
A-7	04/01/07	04/30/07	A-30/360	761136AG5	896,608.00	1,000.000000	5.000000	0.000000	5.000000	1,000.000000
A-8	04/01/07	04/30/07	A-30/360	761136AH3	72,273,000.00	955.000008	4.775000	14.999997	19.774997	940.000011
A-9	04/01/07	04/30/07	A-30/360	761136AJ9	72,273,000.00	955.000009	4.576042	14.999997	19.576039	940.000011
A-10	04/01/07	04/30/07	A-30/360	761136AK6	3,011,375.00	955.000008	4.775001	0.000000	4.775001	940.000010
A-X		761136AM2	330,564,270.00	944.688244	0.433968	0.000000	0.433968	932.461201
PO		761136AL4	1,265,942.00	997.085838	0.000000	1.614537	1.614537	995.471301
B-1	04/01/07	04/30/07	A-30/360	761136AP5	7,732,000.00	998.542005	4.992710	0.488680	5.481389	998.053325
B-2	04/01/07	04/30/07	A-30/360	761136AQ3	4,446,000.00	998.542006	4.992710	0.488680	5.481390	998.053327
B-3	04/01/07	04/30/07	A-30/360	761136AR1	2,319,000.00	998.542005	4.992708	0.488680	5.481389	998.053325
B-4	04/01/07	04/30/07	A-30/360	761136AT7	2,513,000.00	998.542002	4.992710	0.488679	5.481389	998.053323
B-5	04/01/07	04/30/07	A-30/360	761136AU4	1,933,000.00	998.542002	4.992711	0.488681	5.481392	998.053321
B-6	04/01/07	04/30/07	A-30/360	761136AV2	1,352,312.06	998.542008	4.992709	0.488674	5.481383	998.053334
A-R		761136AN0	100.00	0.000000	0.000000	0.000000	0.000000	0.000000




Page 3 of 26

IndyMac Residential Asset Securitization Trust 2007-A1



Mortgage Pass-Through Certificates
Mortgage Pass-Through Certificates
May 25, 2007 Distribution


Distribution to Date -
									Current


	Original		Unscheduled	Scheduled	Total	Total	Realized	Deferred	Principal

Class	Face Value	Interest	Principal	Principal	Principal	Distribution	Loss	Interest	Balance
(1)	(2)	(3)	(4)	(5)=(3)+(4)	(6)=(2)+(5)	(7)	(8)	(9)=(1)-(5)-(7)+(8)
A-1	60,864,674.00	1,217,293.48	0.00	0.00	0.00	1,217,293.48	0.00	0.00	60,864,674.00
A-2	14,162,721.00	283,254.44	0.00	0.00	0.00	283,254.44	0.00	0.00	14,162,721.00
A-3	123,364,500.00	2,314,567.96	12,158,615.58	318,214.64	12,476,830.22	14,791,398.18	0.00	0.00	110,887,669.78
A-4	0.00	0.00	0.00	0.00	0.00	0.00	0.00	0.00	0.00
A-5	21,181,500.00	384,465.14	2,087,616.10	54,636.98	2,142,253.08	2,526,718.22	0.00	0.00	19,039,246.92
A-6	0.00	116,686.56	0.00	0.00	0.00	116,686.56	0.00	0.00	0.00
A-7	896,608.00	17,932.16	0.00	0.00	0.00	17,932.16	0.00	0.00	896,608.00
A-8	72,273,000.00	1,412,937.16	4,177,222.28	159,156.90	4,336,379.18	5,749,316.34	0.00	0.00	67,936,620.82
A-9	72,273,000.00	1,354,064.77	4,177,222.28	159,156.90	4,336,379.18	5,690,443.95	0.00	0.00	67,936,620.82
A-10	0.00	58,872.39	0.00	0.00	0.00	58,872.39	0.00	0.00	0.00
A-X	0.00	597,362.21	0.00	0.00	0.00	597,362.21	0.00	0.00	0.00
PO	1,265,942.00	0.00	2,126.05	3,607.02	5,733.07	5,733.07	0.00	0.00	1,260,208.93
B-1	7,732,000.00	154,527.33	0.00	15,051.69	15,051.69	169,579.02	0.00	0.00	7,716,948.31
B-2	4,446,000.00	88,855.22	0.00	8,654.91	8,654.91	97,510.13	0.00	0.00	4,437,345.09
B-3	2,319,000.00	46,346.21	0.00	4,514.34	4,514.34	50,860.55	0.00	0.00	2,314,485.66
B-4	2,513,000.00	50,223.38	0.00	4,892.00	4,892.00	55,115.38	0.00	0.00	2,508,108.00
B-5	1,933,000.00	38,631.83	0.00	3,762.93	3,762.93	42,394.76	0.00	0.00	1,929,237.07
B-6	1,352,312.06	27,026.54	0.00	2,632.48	2,632.48	29,659.02	0.02	0.00	1,349,679.56
A-R	100.00	0.50	97.24	2.76	100.00	100.50	0.00	0.00	0.00

Total	386,577,357.06	8,163,047.28	22,602,899.53	734,283.55	23,337,183.08	31,500,230.36	0.02	0.00	363,240,173.96


Interest Detail -
	Pass	Prior Principal		Non-	Prior	Unscheduled		Paid or	Current
	Pass	Prior Principal		Non-	Prior	Unscheduled		Paid or

	Through	(with Notional)	Accrued	Supported	Unpaid	Interest	Optimal	Deferred	Unpaid

Class	Rate	Balance	Interest	Interest SF	Interest	Adjustment	Interest	Interest	Interest
			(1)	(2)	(3)	(4)	(5)=(1)-(2)+(3)+(4)	(6)	(7)=(5)-(6)
A-1	6.00000%	60,864,674.00	304,323.37	0.00	0.00	0.00	304,323.37	304,323.37	0.00
A-2	6.00000%	14,162,721.00	70,813.61	0.00	0.00	0.00	70,813.61	70,813.61	0.00
A-3	5.75000%	113,165,647.96	542,252.06	0.00	0.00	0.00	542,252.06	558,283.86	0.00
A-4	0.00000%	113,165,647.96	0.00	0.00	0.00	0.00	0.00	0.00	0.00
A-5	5.72000%	19,430,372.37	92,618.11	0.00	0.00	0.00	92,618.11	92,618.11	0.00
A-6	1.73604%	19,430,372.37	28,109.93	0.00	0.00	0.00	28,109.93	28,109.93	0.00
A-7	6.00000%	896,608.00	4,483.04	0.00	0.00	0.00	4,483.04	4,483.04	0.00
A-8	6.00000%	69,020,715.61	345,103.58	0.00	0.00	0.00	345,103.58	345,103.58	0.00
A-9	5.75000%	69,020,715.62	330,724.26	0.00	0.00	0.00	330,724.26	330,724.26	0.00
A-10	6.00000%	2,875,863.15	14,379.32	0.00	0.00	0.00	14,379.32	14,379.32	0.00
A-X	0.55125%	312,280,179.90	143,454.42	0.00	0.00	0.00	143,454.42	143,454.42	0.00
PO	0.00000%	1,262,252.84	0.00	0.00	0.00	0.00	0.00	0.00	0.00
B-1	6.00000%	7,720,726.78	38,603.63	0.00	0.00	0.00	38,603.63	38,603.63	0.00
B-2	6.00000%	4,439,517.76	22,197.59	0.00	0.00	0.00	22,197.59	22,197.59	0.00
B-3	6.00000%	2,315,618.91	11,578.09	0.00	0.00	0.00	11,578.09	11,578.09	0.00
B-4	6.00000%	2,509,336.05	12,546.68	0.00	0.00	0.00	12,546.68	12,546.68	0.00
B-5	6.00000%	1,930,181.69	9,650.91	0.00	0.00	0.00	9,650.91	9,650.91	0.00
B-6	6.00000%	1,350,340.40	6,751.70	0.00	0.00	0.00	6,751.70	6,751.70	0.00
A-R	0.00000%	0.00	0.00	0.00	0.00	0.00	0.00	0.00	0.00


Total		815,841,492.37	1,977,590.30	0.00	0.00	0.00	1,977,590.30	1,993,622.10	0.00



Page 4 of 26

IndyMac Residential Asset Securitization Trust 2007-A1

Mortgage Pass-Through Certificates

May 25, 2007 Distribution

Collection Account Report

SUMMARY

Total

Principal Collections

4,849,255.03

Principal Withdrawals

0.00

Principal Other Accounts

0.00

TOTAL NET PRINCIPAL

4,849,255.03

Interest Collections

1,995,156.73

Interest Withdrawals

-0.00

Interest Other Accounts

16,031.80

Interest Fees

-17,566.43

TOTAL NET INTEREST

1,993,622.10

TOTAL AVAILABLE FUNDS FOR DISTRIBUTION

6,842,877.13

PRINCIPAL - COLLECTIONS

Total

Scheduled Principal Received

180,429.49

Curtailments

18,315.58

Prepayments In Full

4,650,509.96

Repurchased/Substitutions

0.00

Liquidations

0.00

Insurance Principal

0.00

Other Additional Principal

0.00

Delinquent Principal

-145,068.71

Realized Losses

-0.00

Advanced Principal

145,068.71

TOTAL PRINCIPAL COLLECTED

4,849,255.03

PRINCIPAL - WITHDRAWALS

SPACE INTENTIONALLY LEFT BLANK

PRINCIPAL - OTHER ACCOUNTS

Total

TOTAL PRINCIPAL OTHER ACCOUNTS

0.00

Page 5 of 26

IndyMac Residential Asset Securitization Trust 2007-A1

Mortgage Pass-Through Certificates

May 25, 2007 Distribution

INTEREST - COLLECTIONS

Total

Scheduled Interest

2,046,075.85

Repurchased/Substitution Interest

0.00

Liquidation Interest

0.00

Insurance Interest

0.00

Other Additional Interest

0.00

Prepayment Interest Shortfalls

-3,914.25

Delinquent Interest

-1,635,002.92

Compensating Interest

3,914.25

Civil Relief Act Shortfalls

0.00

Interest Advanced

1,584,083.80

TOTAL INTEREST COLLECTED

1,995,156.73

INTEREST - WITHDRAWALS

Total

Interest Withdrawals

0.00

INTEREST - OTHER ACCOUNTS

Total

Withdrawl from Supplemental Reserve

16,031.80

TOTAL INTEREST OTHER ACCOUNTS

16,031.80

INTEREST FEES

Total

Current Servicing Fees

12,844.87

Trustee Fees

2,607.30

PMI

2,114.28

TOTAL INTEREST FEES

17,566.43

Page 6 of 26

IndyMac Residential Asset Securitization Trust 2007-A1

Mortgage Pass-Through Certificates

May 25, 2007 Distribution

Credit Enhancement Report

ACCOUNTS

Supplemental Interest Reserve Fund

Beginning Account Balance

1,416.54

Amounts received from Counterparty

16,864.71

Yield Supplement Amount Paid

16,031.80

Ending Account Balance

2,249.45

INSURANCE

SPACE INTENTIONALLY LEFT BLANK

STRUCTURAL FEATURES

SPACE INTENTIONALLY LEFT BLANK

Page 7 of 26

IndyMac Residential Asset Securitization Trust 2007-A1

Mortgage Pass-Through Certificates

May 25, 2007 Distribution

Collateral Report

COLLATERAL

Total

Loan Count:

Original

636

Prefunding

Substitution Loans

Scheduled Paid Offs

-0

Full Voluntary Prepayments

-7

Repurchases

-0

Liquidations

-0

Current

602

Principal Balance:

Original

386,577,357.06

Prior

368,089,428.99

Prefunding

0.00

Substitution Loans

0.00

Scheduled Principal

-180,429.49

Partial Prepayments

-18,315.58

Full Voluntary Prepayments

-4,650,509.96

Repurchases

-0.00

Liquidations

-0.00

Current

363,240,173.96

PREFUNDING

SPACE INTENTIONALLY LEFT BLANK

Page 8 of 26

IndyMac Residential Asset Securitization Trust 2007-A1

Mortgage Pass-Through Certificates

May 25, 2007 Distribution



CHARACTERISTICS
CHARACTERISTICS

							Total
Weighted Average Coupon Original							6.69417%
Weighted Average Coupon Prior							6.67352%
Weighted Average Coupon Current							6.67037%
Weighted Average Months to Maturity Original							357
Weighted Average Months to Maturity Prior							356
Weighted Average Months to Maturity Current							355
Weighted Avg Remaining Amortization Term Original							360
Weighted Avg Remaining Amortization Term Prior							358
Weighted Avg Remaining Amortization Term Current							358
Weighted Average Seasoning Original							2.01
Weighted Average Seasoning Prior							3.99
Weighted Average Seasoning Current							4.99

Page 9 of 26

IndyMac Residential Asset Securitization Trust 2007-A1

Mortgage Pass-Through Certificates

May 25, 2007 Distribution



ARM CHARACTERISTICS
ARM CHARACTERISTICS

							Total
Weighted Average Margin Original							0.00000%
Weighted Average Margin Prior							0.00000%
Weighted Average Margin Current							0.00000%
Weighted Average Max Rate Original							0.00000%
Weighted Average Max Rate Prior							0.00000%
Weighted Average Max Rate Current							0.00000%
Weighted Average Min Rate Original							0.00000%
Weighted Average Min Rate Prior							0.00000%
Weighted Average Min Rate Current							0.00000%
Weighted Average Cap Up Original							0.00000%
Weighted Average Cap Up Prior							0.00000%
Weighted Average Cap Up Current							0.00000%
Weighted Average Cap Down Original							0.00000%
Weighted Average Cap Down Prior							0.00000%
Weighted Average Cap Down Current							0.00000%





Page 10 of 26

IndyMac Residential Asset Securitization Trust 2007-A1

Mortgage Pass-Through Certificates

May 25, 2007 Distribution

SERVICING FEES & ADVANCES

Total

Current Servicing Fees

12,844.87

Delinquent Servicing Fees

50,919.11

TOTAL SERVICING FEES

63,763.99

Total Servicing Fees

63,763.99

Compensating Interest

-3,914.25

Delinquent Servicing Fees

-50,919.11

COLLECTED SERVICING FEES

8,930.62

Total Advanced Interest

1,584,083.80

Total Advanced Principal

145,068.71

Aggregate Advances with respect to this Distribution

1,729,152.51

Aggregate Advances Outstanding on the close of distribution

0.00

ADDITIONAL COLLATERAL INFORMATION

Total

Prepayment Interest Shortfall (PPIS)

3,914.25

Compensating Interest

(3,914.25)

Net Prepayment Interest Shortfall (PPIS)

0.00

Weighted Average Net Mortgage Rate

6.447097%

Page 11 of 26

IndyMac Residential Asset Securitization Trust 2007-A1



Mortgage Pass-Through Certificates
Mortgage Pass-Through Certificates
May 25, 2007 Distribution

Delinquency Report

TOTAL
		< 1 PAYMENT	1 PAYMENT	2 PAYMENTS	3+ PAYMENTS	TOTAL
DELINQUENT	Balance		9,192,750.81	1,691,644.89	1,967,465.85	12,851,861.55
	% Balance		2.53%	0.47%	0.54%	3.54%
	# Loans		15	3	4	22
	% # Loans		2.49%	0.50%	0.66%	3.65%
FORECLOSURE	Balance	0.00	0.00	0.00	0.00	0.00
	% Balance	0.00%	0.00%	0.00%	0.00%	0.00%
	# Loans	0	0	0	0	0
	% # Loans	0.00%	0.00%	0.00%	0.00%	0.00%
BANKRUPTCY	Balance	0.00	0.00	0.00	0.00	0.00
	% Balance	0.00%	0.00%	0.00%	0.00%	0.00%
	# Loans	0	0	0	0	0
	% # Loans	0.00%	0.00%	0.00%	0.00%	0.00%
REO	Balance	0.00	0.00	0.00	0.00	0.00
	% Balance	0.00%	0.00%	0.00%	0.00%	0.00%
	# Loans	0	0	0	0	0
	% # Loans	0.00%	0.00%	0.00%	0.00%	0.00%
TOTAL	Balance	0.00	9,192,750.81	1,691,644.89	1,967,465.85	12,851,861.55
	% Balance	0.00%	2.53%	0.47%	0.54%	3.54%
	# Loans	0	15	3	4	22
	% # Loans	0.00%	2.49%	0.50%	0.66%	3.65%

Page 12 of 26

IndyMac Residential Asset Securitization Trust 2007-A1

Mortgage Pass-Through Certificates

May 25, 2007 Distribution

REO Report

Loan Number

Original

Stated

Current

State &

First

Principal

Paid to

Note

LTV at

Original

Payment

Loan Group

Balance

Date

Rate

Origination

Term

Date

Page 13 of 26

IndyMac Residential Asset Securitization Trust 2007-A1

Mortgage Pass-Through Certificates

May 25, 2007 Distribution

Foreclosure Report

Loan Number

Original

Stated

Current

State &

First

Principal

Paid to

Note

LTV at

Original

Payment

Loan Group

Balance

Date

Rate

Origination

Term

Date

Page 14 of 26

IndyMac Residential Asset Securitization Trust 2007-A1

Mortgage Pass-Through Certificates

May 25, 2007 Distribution

Prepayment Report

VOLUNTARY PREPAYMENTS

Total

Current

Number of Paid in Full Loans

Number of Repurchased Loans

Total Number of Loans Prepaid in Full

Curtailments Amount

18,315.58

Paid in Full Balance

4,650,509.96

Repurchased Loans Balance

0.00

Total Prepayment Amount

4,668,825.54

Cumulative

Number of Paid in Full Loans

Number of Repurchased Loans

Total Number of Loans Prepaid in Full

Paid in Full Balance

21,920,557.54

Repurchased Loans Balance

0.00

Curtailments Amount

682,341.99

Total Prepayment Amount

22,602,899.53

Page 15 of 26

IndyMac Residential Asset Securitization Trust 2007-A1



Mortgage Pass-Through Certificates
Mortgage Pass-Through Certificates
May 25, 2007 Distribution


VOLUNTARY PREPAYMENTS RATES - Including Liquidated Balances



		Total





SMM	1.27%
3 Months Avg SMM	1.45%
12 Months Avg SMM	1.50%
Avg SMM Since Cut-off	1.50%



CPR	14.21%
3 Months Avg CPR	16.10%
12 Months Avg CPR	16.55%
Avg CPR Since Cut-off	16.55%



PSA	1,424.43%
3 Months Avg PSA Approximation	2,016.81%
12 Months Avg PSA Approximation	2,367.65%
Avg PSA Since Cut-off Approximation	2,367.65%


(*) SMM, CPR, PSA Figures Include Liquidated Balances

Page 16 of 26

IndyMac Residential Asset Securitization Trust 2007-A1

Mortgage Pass-Through Certificates

May 25, 2007 Distribution

PREPAYMENT CALCULATION METHODOLOGY - Including Liquidated Balances

Single Monthly Mortality (SMM): (Voluntary partial and full prepayments + Repurchases + Liquidated Balances)/(Beg Principal Balance - Sched Principal)

Conditional Prepayment Rate (CPR): 1-((1-SMM)^12)

PSA Standard Prepayment Model: CPR/(0.20%*min(30,WAS))

Average SMM over period between nth month and mth month (AvgSMMn,m): 1 - [(1-SMMn)*(1-SMMn+1)*...*(1-SMMm)]^(1/months in period n,m)

Average CPR over period between the nth month and mth month (AvgCPRn,m): 1-((1-AvgSMMn,m)^12)

Average PSA Approximation over period between the nth month and mth month: AvgCPRn,m/(0.20%*Avg WASn,m))

Average WASn,m: (min(30,WASn)+min(30,WASn+1)+...+min(30,WASm)/(number of months in the period n,m)

Weighted Average Seasoning (WAS)

Note: Prepayment rates are calculated since deal issue date and include partial and full voluntary prepayments and repurchases.

Dates correspond to distribution dates.

Page 17 of 26

IndyMac Residential Asset Securitization Trust 2007-A1

Mortgage Pass-Through Certificates

May 25, 2007 Distribution

VOLUNTARY PREPAYMENTS RATES - Excluding Liquidated Balances

Total

SMM

1.27%

3 Months Avg SMM

1.45%

12 Months Avg SMM

1.50%

Avg SMM Since Cut-off

1.50%

CPR

14.21%

3 Months Avg CPR

16.10%

12 Months Avg CPR

16.55%

Avg CPR Since Cut-off

16.55%

PSA

1,424.43%

3 Months Avg PSA Approximation

2,016.81%

12 Months Avg PSA Approximation

2,367.65%

Avg PSA Since Cut-off Approximation

2,367.65%

(*) SMM, CPR, PSA Figures Exclude Liquidated Balances

Page 18 of 26

IndyMac Residential Asset Securitization Trust 2007-A1

Mortgage Pass-Through Certificates

May 25, 2007 Distribution

PREPAYMENT CALCULATION METHODOLOGY - Excluding Liquidated Balances

Single Monthly Mortality (SMM): (Voluntary partial and full prepayments + Repurchases)/(Beg Principal Balance - Sched Principal)

Conditional Prepayment Rate (CPR): 1-((1-SMM)^12)

PSA Standard Prepayment Model: CPR/(0.20%*min(30,WAS))

Average SMM over period between nth month and mth month (AvgSMMn,m): 1 - [(1-SMMn)*(1-SMMn+1)*...*(1-SMMm)]^(1/months in period n,m)

Average CPR over period between the nth month and mth month (AvgCPRn,m): 1-((1-AvgSMMn,m)^12)

Average PSA Approximation over period between the nth month and mth month: AvgCPRn,m/(0.20%*Avg WASn,m))

Average WASn,m: (min(30,WASn)+min(30,WASn+1)+...+min(30,WASm)/(number of months in the period n,m)

Weighted Average Seasoning (WAS)

Note: Prepayment rates are calculated since deal issue date and include partial and full voluntary prepayments and repurchases.

Dates correspond to distribution dates.

Page 19 of 26

IndyMac Residential Asset Securitization Trust 2007-A1

Mortgage Pass-Through Certificates

May 25, 2007 Distribution

Prepayment Detail Report

Prepayment Detail Report - Mortgage Loans Prepaid in Full During Current Distribution

Loan Number

Original

Current

State &

Type Prepayment

First

Loan

Principal

Prepayment

Note

LTV at

Payment

Loan Group

Status

Balance

Amount

Date

Rate

Origination

Original Term

Date

6056433 1

540,000.00

534,782.29

17-Apr-2007

6.750%

AZ - 74.48%

Paid Off - 360

01-Jul-2006

6069407 1

547,500.00

545,338.50

10-May-2007

7.250%

OR - 75.00%

Paid Off - 360

01-Dec-2006

6075749 1

898,150.00

23-Apr-2007

6.500%

AZ - 80.00%

Paid Off - 360

01-Jan-2007

124831704 1

484,649.00

482,882.19

14-May-2007

6.500%

MD - 80.00%

Paid Off - 360

01-Jan-2007

124962937 1

427,192.00

426,082.38

08-May-2007

6.750%

CA - 80.00%

Paid Off - 360

01-Feb-2007

125016189 1

768,750.00

765,809.44

01-May-2007

6.250%

CA - 75.00%

Paid Off - 360

01-Jan-2007

125142932 1

1,000,000.00

997,465.16

24-Apr-2007

6.875%

CA - 58.82%

Paid Off - 360

01-Feb-2007

TOTAL

4,666,241.00

4,650,509.96

Page 20 of 26

IndyMac Residential Asset Securitization Trust 2007-A1

Mortgage Pass-Through Certificates

May 25, 2007 Distribution

Realized Loss Report

COLLATERAL REALIZED LOSSES

Total

Current

Subsequent Recoveries

Number of Loans Liquidated

Collateral Principal Realized Loss/(Gain) Amount

0.00

Collateral Interest Realized Loss/(Gain) Amount

0.00

Net Liquidation Proceeds

0.00

Cumulative

Number of Loans Liquidated

Collateral Realized Loss/(Gain) Amount

0.00

Net Liquidation Proceeds

0.00

Cumulative Subsequent Recoveries

Special Hazard Loss Coverage Amt

5,426,272.84

Fraud Loss Coverage Amt

7,731,547.00

Bankrupt Loss Coverage Amt

133,025.00

Class B-1 Writedown Amount

0.00

Class B-2 Writedown Amount

0.00

Class B-3 Writedown Amount

0.00

Class B-4 Writedown Amount

0.00

Class B-5 Writedown Amount

0.00

Class B-6 Writedown Amount

0.00

Page 21 of 26

IndyMac Residential Asset Securitization Trust 2007-A1



Mortgage Pass-Through Certificates
Mortgage Pass-Through Certificates
May 25, 2007 Distribution


DEFAULT SPEEDS
DEFAULT SPEEDS
								Total




MDR								0.00%
3 Months Avg MDR								0.00%
12 Months Avg MDR								0.00%
Avg MDR Since Cut-off								0.00%


CDR								0.00%
3 Months Avg CDR								0.00%
12 Months Avg CDR								0.00%
Avg CDR Since Cut-off								0.00%


SDA								0.00%
3 Months Avg SDA Approximation								0.00%
12 Months Avg SDA Approximation								0.00%
Avg SDA Since Cut-off Approximation								0.00%


Principal Only Loss Severity Approx for Current Period								0.00%
3 Months Avg Loss Severity Approximation								0.00%
12 Months Avg Loss Severity Approximation								0.00%
Avg Loss Severity Approximation Since Cut-Off								0.00%


Principal & Interest Loss Severity Approx for Current Period								0.00%
3 Months Avg Loss Severity Approximation								0.00%
12 Months Avg Loss Severity Approximation								0.00%
Avg Loss Severity Approximation Since Cut-Off								0.00%

Page 22 of 26

IndyMac Residential Asset Securitization Trust 2007-A1

Mortgage Pass-Through Certificates

May 25, 2007 Distribution

COLLATERAL REALIZED LOSS CALCULATION METHODOLOGY

Monthly Default Rate (MDR): (Beg Principal Balance of Liquidated Loans)/(Total Beg Principal Balance)

Conditional Default Rate (CDR): 1-((1-MDR)^12)

SDA Standard Default Assumption: CDR/IF(WAS<61,MIN(30,WAS)*0.02%,MAX(0.03%,MIN(30,WAS)*0.02%-0.0095%*(WAS-60)))

Average MDR over period between nth month and mth month (AvgMDRn,m): [(1-MDRn)*(1-MDRn+1)*...*(1-MDRm)]^(1/months in period n,m)

Average CDR over period between the nth month and mth month (AvgCDRn,m): 1-((1-AvgMDRn,m)^12)

Average SDA Approximation over period between the nth month and mth month:

AvgCDRn,m/IF(Avg WASn,m<61,MIN(30,Avg WASn,m)*0.02%,MAX(0.03%,MIN(30,Avg WASn,m)*0.02%-0.0095%*(Avg WASn,m-60)))

Average WASn,m: (WASn + WASn+1 +...+ WASm )/(number of months in the period n,m)

Principal Only Loss Severity Approximation for current period:

Sum(Principal Realized Loss Amount)/sum(Beg Principal Balance of Liquidated Loans)

Principal & Interest Loss Severity Approximation for current period:

Sum(Principal & Interest Realized Loss Amount)/sum(Beg Principal Balance of Liquidated Loans)

Average Loss Severity Approximation over period between nth month and mth month:

Sum(Realized Loss Amount)/sum(Beg Principal Balance of Liquidated Loans for months in the period n,m

Note: Default rates are calculated since deal issue date and include realized gains and additional realized losses and gains from prior periods.

Dates correspond to distribution dates.

All Realized Losses in excess of Principal Balance are treated as Interest Realized Losses.

Page 23 of 26

IndyMac Residential Asset Securitization Trust 2007-A1

Mortgage Pass-Through Certificates

May 25, 2007 Distribution

Realized Loss Detail Report

Loan Number

Current

State &

Prior

Realized

Cumulative

Loan

Note

LTV at

Original

Principal

Loss/(Gain)

Realized

Loan Group

Status

Rate

Origination

Term

Balance

Revision

Loss/(Gain)

TOTAL

Page 24 of 26

IndyMac Residential Asset Securitization Trust 2007-A1

Mortgage Pass-Through Certificates

May 25, 2007 Distribution

Triggers and Adj. Cert. Report

TRIGGER EVENTS

Total

Has Optional Termination Date Reached ?

Has Sr. Credit Supp. Depletion Date Occured ?

Has Special Haz. Cov. Term Date Occured ?

Has Fraud Loss Coverage Term Date Occured ?

Has BK Loss Cov. Term Date Occured ?

Does an Event of Default Exist?

Senior Stepdown Date has occurred?

Sr.Stepdown Cond Satisfied?(1=Yes or 2=Yes)

1.Delinquency Trigger

Does Delinquency Trigger Event Exist (a > 50% of b)

(a) Rolling Six Month 60+ Delq Balance

1,161,979.22

(b) Aggregate Balance of Subordinate Certificates

20,255,803.69

2.Cumulative Loss Trigger

Does a Loss Trigger Event Exist (a > b)

(a) Cumulative Realized Loss

0.00

(b) Cumulative Loss Threshold (i)*(ii)

0.00

(i) Threshold Percentage

0.0000%

(ii) Cutoff Date Subordinate Principal Balance

20,295,312.06

ADJUSTABLE RATE CERTIFICATE INFORMATION

SPACE INTENTIONALLY LEFT BLANK

ADDITIONAL INFORMATION

Total

Senior Percentage

94.475403%

Subordinate Percentage

5.524597%

Senior Prepayment Percentage

100.000000%

Subordinate Prepayment Percentage

0.000000%

Current LIBOR Rate

5.320000%

Libor Rate Determination Date

04/23/2007

Next LIBOR Rate

5.320000%

Next Libor Determination Date

05/23/2007

Page 25 of 26

IndyMac Residential Asset Securitization Trust 2007-A1



Mortgage Pass-Through Certificates
Mortgage Pass-Through Certificates
May 25, 2007 Distribution

Other Related Information
ADDITIONAL INFORMATION
ADDITIONAL INFORMATION
							Total
Current Scheduled Payments							2,226,505.34
Current Scheduled Payments 1 Month Prior							2,244,445.59
Current Scheduled Payments 2 Month Prior							2,296,598.75
Current Scheduled Payments 3 Month Prior							2,346,245.67
Current Scheduled Payments 4 Month Prior							0.00
Current Scheduled Payments 5 Month Prior							0.00
Current Scheduled Payments 6 Month Prior							0.00
Current Scheduled Payments 7 Month Prior							0.00
Current Scheduled Payments 8 Month Prior							0.00
Current Scheduled Payments 9 Month Prior							0.00
Current Scheduled Payments 10 Month Prior							0.00
Current Scheduled Payments 11 Month Prior



Delinquent 60+ Scheduled Payments							23,439.39
Delinq. 60+ Sched. Pmnts, 1 Month Prior							18,795.09
Delinq. 60+ Sched. Pmnts, 2 Month Prior							2,807.41
Delinq. 60+ Sched. Pmnts, 3 Month Prior							0.00
Delinq. 60+ Sched. Pmnts, 4 Month Prior							0.00
Delinq. 60+ Sched. Pmnts, 5 Month Prior							0.00
Delinq. 60+ Sched. Pmnts, 6 Month Prior							0.00
Delinq. 60+ Sched. Pmnts, 7 Month Prior							0.00
Delinq. 60+ Sched. Pmnts, 8 Month Prior							0.00
Delinq. 60+ Sched. Pmnts, 9 Month Prior							0.00
Delinq. 60+ Sched. Pmnts, 10 Month Prior							0.00
Delinq. 60+ Sched. Pmnts, 11 Month Prior





Page 26 of 26

Residential Asset Securitization Trust 2007-A1 10-D