Exhibit 21

SUBSIDIARIES OF THE COMPANY

|                                                     |  | State of Organization
|---------------------------------------------------- |  | ---------------------
|Corporations                                         |  |                      
|American Spectrum Realty Management, Inc.            |  | Delaware             
|American Spectrum Realty Properties, Inc.            |  | Maryland             
|ASR Sam Houston I, Inc.                              |  | Texas                
|Limited Partnerships                                 |  |                      
|American Spectrum Holdings-Hazelwood, L.P.           |  | Missouri             
|American Spectrum Realty Operating Partnership, L.P. |  | Delaware             
|ASR Park Ten 350, L.P.                               |  | Texas                
|ASR Park Ten 360, L.P.                               |  | Texas                
|ASR 800 Sam Houston, L.P.                            |  | Delaware             
|ASR 5450 NW, L.P.                                    |  | Delaware             
|ASR 5850 San Felipe, L.P.                            |  | Delaware             
|ASR Sam Houston, L.P.                                |  | Texas                
|ASR Washington, L.P.                                 |  | Texas                
|ASR Westheimer, L.P.                                 |  | Texas                
|Lindbergh Boulevard Partners                         |  | Missouri             
|Market Columbia, L.P.                                |  | California           
|Nooney Rider Trail, L.P.                             |  | Delaware             
|Pasadena Autumn Ridge, L.P.                          |  | Texas                
|Sierra Pacific Development Fund II, L.P.             |  | Delaware             
|Limited Liability Companies                          |  |                      
|American Spectrum Holdings (CGS), LLC                |  | Delaware             
|American Spectrum Holdings (Lindbergh), LLC          |  | Delaware             
|American Spectrum Holdings (Pasadena), LLC           |  | Delaware             
|American Spectrum Holdings (SPIP-V), LLC             |  | Delaware             
|American Spectrum Holdings (Washington), LLC         |  | Delaware             
|American Spectrum Holdings (Westheimer), LLC         |  | Delaware             
|ASR 800 Sam Houston, LLC                             |  | Delaware             
|ASR 5450, LLC                                        |  | Delaware             
|ASR 5850 San Felipe, LLC                             |  | Delaware             
|ASR NRT, LLC                                         |  | Delaware             
|Back Bay, LLC                                        |  | Delaware             
|Countryside Exec Center, LLC                         |  | Delaware             
|Leawood, LLC                                         |  | Delaware             
|Leawood KS, LLC                                      |  | Delaware             
|Market Columbia, LLC                                 |  | Delaware             
|McDonnell Associates, LLC                            |  | Delaware             
|Nooney Income Fund II, LLC                           |  | Delaware             
|Nooney Income Fund, LLC                              |  | Delaware             
|Nooney Real Property Investors Two, LLC              |  | Delaware             
|Nooney Rider Trail, LLC                              |  | Delaware             
|Northcreek, LLC                                      |  | Delaware             
|Oakgrove Commons, LLC                                |  | Delaware             
|Pacific Spectrum, LLC                                |  | Arizona              
|Plaza Center, LLC                                    |  | Delaware             
|Seventy Seven, LLC                                   |  | Delaware             
|Sierra Creekside, LLC                                |  | Delaware             
|Sierra Pacific Development Fund II, LLC              |  | Delaware             
|                                                     |  |                      

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|SUBSIDIARIES OF THE COMPANY (continued)  |  |           
|---------------------------------------- |  | ----------
|Sierra Pacific Development Fund III, LLC |  | Delaware  
|Sierra Pacific Development Fund, LLC     |  | Delaware  
|Sierra Pacific Pension Investors 84, LLC |  | Delaware  
|Sierra Southwest Pointe LLC              |  | Delaware  
|Sorrento II, LLC                         |  | Delaware  
|Third Coast, LLC                         |  | Delaware  
|Partnerships                             |  |           
|Sierra Creekside Partners                |  | California
|Sierra Mira Mesa Partners                |  | California
|Sorrento I Partners                      |  | California
|Sorrento II Partners                     |  | California

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