Exhibit 21

Subsidiaries of the Registrant

The following are subsidiaries of the Registrant as of
December 31, 2007 and the jurisdiction in which each is organized. Each of the subsidiaries generally conducts its business using names indicated. Certain subsidiaries are not listed; these omitted subsidiaries individually and in the aggregate
do not constitute a significant subsidiary.



|                                                  |  |                                 
|------------------------------------------------- |  | --------------------------------
|Subsidiaries of Hill International, Inc.          |  | State or Country of Organization
|Transportation Construction Services, Inc.        |  | Delaware                        
|Hill International (Puerto Rico), Inc.            |  | Delaware                        
|KJM & Associates, Ltd.                            |  | Washington                      
|Stanley Baker Hill, LLC*                          |  | Delaware                        
|Hill International S.A.*                          |  | Luxembourg                      
|Hill International Development Ltd.               |  | British Virgin Islands          
|Hill International Development (II) Ltd.          |  | British Virgin Islands          
|                                                  | 
|Subsidiaries of Hill International S.A.           |  |                                 
|Hill International (Anatolia)                     |  | Turkey                          
|SIA Hill International (Baltic)                   |  | Latvia                          
|Hill International Services Ltd.                  |  | British Virgin Islands          
|Hill International (UK) Ltd.*                     |  | England                         
|Hill International (Bucharest) S.R.L.             |  | Romania                         
|Hill International (Hellas) S.A.                  |  | Greece                          
|Hill International (Middle East) Ltd.             |  | British Virgin Islands          
|Hill Construction Management Ltd.                 |  | Serbia                          
|Hill International Rijeka d.o.o.                  |  | Croatia                         
|James R. Knowles (Holdings) Ltd.*                 |  | England                         
|Hill International (Libya) Ltd.                   |  | Malta                           
|Hill International (North Africa) Ltd.            |  | Egypt                           
|Asia/Pacific Hill International Holding Pte Ltd.  |  | Singapore                       
|                                                  | 
|Subsidiary of Hill International (UK) Ltd.        |  |                                 
|Pickavance Group Ltd.                             |  | England                         
|                                                  | 
|Subsidiaries of James R. Knowles (Holdings) Ltd.  |  |                                 
|James R. Knowles Global Ltd.*                     |  | England                         
|James R. Knowles (Worldwide) Ltd.*                |  | England                         
|James R. Knowles (Australian Holdings) Pty. Ltd.* |  | Australia                       
|Knowles North American Holdings Inc.*             |  | Canada                          
|Knowles Consultancy Services, Inc.                |  | Canada                          
|                                                  | 
|Subsidiary of John Shreeves Holdings Ltd.         |  |                                 
|John Shreeves & Partners Ltd.                     |  | England                         



|* | Parent corporation of additional subsidiaries
|- | ---------------------------------------------