Exhibit 21

WATSON WYATT WORLDWIDE, INC.        SUBSIDIARIES        (9-30-07)

|SUBSIDIARY NAME                                     |  | JURISDICTION OF
INCORPORATION/ ORGANIZATION
|--------------------------------------------------- |  | -------------------------------------------
|Watson Wyatt Argentina S.A.                         |  | Argentina                                  
|Watson Wyatt Australia Pty Ltd                      |  | Australia                                  
|Wycomp Pty Ltd                                      |  | Australia                                  
|Watson Wyatt Superannuation Pty Ltd                 |  | Australia                                  
|Watson Wyatt (Austria) GmbH                         |  | Austria                                    
|Watson Wyatt Insurance and Financial Services SA    |  | Belgium                                    
|Watson Wyatt NV                                     |  | Belgium                                    
|Watson Wyatt Brasil Ltda                            |  | Brazil                                     
|Watson Wyatt Canada ULC                             |  | Canada                                     
|Watson Wyatt Chile S.A.                             |  | Chile                                      
|Corredores de Seguros Watson Wyatt Limitada         |  | Chile                                      
|Watson Wyatt Consultancy (Shanghai) Ltd             |  | China                                      
|Watson Wyatt Consultancy (Shenzhen) Ltd             |  | China                                      
|Watson Wyatt Consultores Colombia S.A.              |  | Colombia                                   
|Watson Wyatt Colombia S.A.                          |  | Colombia                                   
|Watson Wyatt & Company                              |  | Delaware                                   
|Wyatt Data Services, Inc.                           |  | Delaware                                   
|Watson Wyatt Investment Consulting, Inc.            |  | Delaware                                   
|Watson Wyatt Insurance Consulting, Inc.             |  | Delaware                                   
|Watson Wyatt Insurance and Financial Services, Inc. |  | Delaware                                   
|Watson Wyatt Canadian Holdings, Inc.                |  | Delaware                                   
|Watson Wyatt European Investment Holdings, Inc.     |  | Delaware                                   
|Watson Wyatt European Investment Holdings 1, LLC    |  | Delaware                                   
|Watson Wyatt European Investment Holdings 2, LLC    |  | Delaware                                   
|Watson Wyatt SARL                                   |  | France                                     
|Watson Wyatt (France) Sarl                          |  | France                                     
|Buck Heissmann Sarl 2                               |  | France                                     
|Watson Wyatt Heissmann (Dussledorf) GmbH            |  | Germany                                    
|Watson Wyatt Heissmann (Munchen-Frankfurt) GmbH     |  | Germany                                    
|Watson Wyatt Insurance Consulting GmbH              |  | Germany                                    
|                                                    |  |                                            

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|Watson Wyatt Heissmann GmbH                          |  | Germany           
|---------------------------------------------------- |  | ------------------
|Buck Heissmann Holdings GmbH                         |  | Germany           
|IPC Heissmann Versicherungsservice GmbH              |  | Germany           
|Verlag Arbeit Und Alter GmbH                         |  | Germany           
|Heissmann Consultants GmbH                           |  | Germany           
|PM&S Pensions-managment und Sicherungs-Treuhand AG   |  | Germany           
|Buck Heissmann GmbH                                  |  | Germany           
|Watson Wyatt Insurance Consulting Ltd                |  | Hong Kong         
|Watson Wyatt Hong Kong Limited                       |  | Hong Kong         
|Watson Wyatt Investment Consulting Hong Kong Limited |  | Hong Kong         
|Watson Wyatt Kft                                     |  | Hungary           
|Watson Wyatt Insurance Consulting Private Ltd        |  | India             
|Watson Wyatt India Private Limited                   |  | India             
|PT Watson Wyatt Purbajaga                            |  | Indonesia         
|PT Watson Wyatt Indonesia                            |  | Indonesia         
|Watson Wyatt (Ireland) Limited                       |  | Ireland           
|Watson Wyatt Consulting Limited                      |  | Ireland           
|BCI Trustees Limited                                 |  | Ireland           
|Watson Wyatt Italia Srl                              |  | Italy             
|Watson Wyatt Insurance Consulting KK                 |  | Japan             
|Watson Wyatt KK                                      |  | Japan             
|Watson Wyatt Insurance Consulting (Korea) Limited    |  | Korea, Republic of
|Watson Wyatt (Malaysia) Sdn Bhd                      |  | Malaysia          
|Watson Wyatt Holdings (Mauritius) Limited            |  | Mauritius         
|Watson Wyatt Mexico, S.A. de C.V.                    |  | Mexico            
|Watson Wyatt European Region BV                      |  | Netherlands       
|Watson Wyatt Insurance Consulting BV                 |  | Netherlands       
|Watson Wyatt BV                                      |  | Netherlands       
|Watson Wyatt (Woerden) B.V.                          |  | Netherlands       
|Watson Wyatt International, Inc.                     |  | Nevada            
|Watson Wyatt Philippines, Inc.                       |  | Philippines       
|Watson Wyatt Puerto Rico, Inc.                       |  | Puerto Rico       
|Watson Wyatt Insurance Consulting Pte Ltd            |  | Singapore         
|Watson Wyatt Singapore Pte Ltd                       |  | Singapore         
|Watson Wyatt Insurance Consulting (Spain) SA         |  | Spain             
|                                                     |  |                   

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|Watson Wyatt de Espana SA                                               |  | Spain         
|----------------------------------------------------------------------- |  | --------------
|Watson Wyatt AB                                                         |  | Sweden        
|Watson Wyatt AG                                                         |  | Switzerland   
|Watson Wyatt (Thailand) Limited                                         |  | Thailand      
|Watson Wyatt Limited                                                    |  | United Kingdom
|Watson Wyatt Holdings Limited                                           |  | United Kingdom
|Watson Wyatt Trustees Limited                                           |  | United Kingdom
|The Wyatt Company Holdings Limited                                      |  | United Kingdom
|Watson Wyatt Services Limited                                           |  | United Kingdom
|Watson Wyatt Pretium Limited                                            |  | United Kingdom
|Watson Wyatt Holdings (Europe) Limited                                  |  | United Kingdom
|Watson Wyatt International Limited                                      |  | United Kingdom
|Watson Wyatt Insurance & Financial Services Consulting Holdings Limited |  | United Kingdom
|Watson Wyatt European Region Limited                                    |  | United Kingdom
|Watson Wyatt European Investment Holdings Limited                       |  | United Kingdom
|Watsons Pensioneer Trustees Limited                                     |  | United Kingdom
|Watson Wyatt (UK) Acquisitions 1 Limited                                |  | United Kingdom
|PCL Limited                                                             |  | United Kingdom
|PCL 1991 Limited                                                        |  | United Kingdom
|Wyatt Trustee Limited                                                   |  | United Kingdom
|The Wyatt Company (UK) Limited                                          |  | United Kingdom
|Wyatt Pension Plan Trustee Limited                                      |  | United Kingdom
|Wyatt Financial Services Limited                                        |  | United Kingdom
|Watsons International Limited                                           |  | United Kingdom
|RWS Trustee Limited                                                     |  | United Kingdom
|Watson Wyatt Healthcare Trustees Limited                                |  | United Kingdom
|Watson Wyatt (UK) Acquisitions 2 Limited                                |  | United Kingdom
|Watson Wyatt European Investment Limited Partnership                    |  | United Kingdom
|Watson Wyatt Uruguay S.A.                                               |  | Uruguay       

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