Holding(s) in Company

TR-1: Notifications of Major Interests in Shares                               

1. Identity of the issuer or the underlying             Serco Group plc        
issuer of existing shares to which voting                                      
rights are attached:                                                           
                                                                               
2. Reason for notification (yes/no)                                            
                                                                               
An acquisition or disposal of voting rights                             Yes    
                                                                               
An acquisition or disposal of financial instruments which may result           
in the acquisition of shares already issued to which voting rights             
are attached                                                                   
                                                                               
An event changing the breakdown of voting rights                               
                                                                               
Other (please specify):______________                                          
                                                                               
3. Full name of person(s) subject to             Baillie Gifford & Co          
notification obligation:                                                       
                                                                               
4. Full name of shareholder(s) (if                                             
different from 3):                                                             
                                                                               
5. Date of transaction (and date on                    09-Dec-08               
which the threshold is crossed or                                              
reached if different):                                                         
                                                                               
6. Date on which issuer notified:                      10-Dec-08               
                                                                               
7. Threshold(s) that is/are crossed or                    5%                   
reached:                                                                       

8: Notified Details                                                              
                                                                                 
A: Voting rights attached to shares                                              
                                                                                 
Class/type  Situation previous  Resulting situation after the triggering         
of shares   to the triggering   transaction                                      
            transaction                                                          
If possible                                                                      
use ISIN                                                                         
code                                                                             
                                                                                 

Number of    Number   Number  Number of voting  Percentage of          
shares       of       of      rights            voting rights          
             voting   shares                                           
             rights                                                    
                              Direct   Indirect Direct   Indirect      
                                                                       
Ordinary     29198382 6.00    28982782          28982782          5.96 
                                                                       
Share                                                                  
                                                                       
GB0007973794                                                           

B: Financial Instruments                                                       
                                                                               
Resulting situation after the triggering transaction                           
                                                                               
Type of        Expiration     Exercise/       No. of voting      Percentage of 
financial      date           conversion      rights that may be voting rights 
instrument                    period/date     acquired (if the                 
                                              instrument                       
                                              exercised/                       
                                              converted)                       
                                                                               
N/A                                                                            

Total (A+B)                                                                    
                                                                               
Number of voting rights                 Percentage of voting rights            
                                                                               
28982782                                5.96                                   

9. Chain of controlled undertakings through which the voting rights and /or the
financial instruments are effectively held, if applicable:                     
                                                                               
In the narrative below, the figures in [ ] indicate the amount of voting rights
and the percentage held by each controlled undertaking where relevant.         
                                                                               
Baillie Gifford & Co, a discretionary investment manager, is the parent        
undertaking of an investment management group.                                 
                                                                               
Its wholly-owned subsidiary undertaking Baillie Gifford Overseas Limited       
[612988; 0.1%] is also a discretionary investment manager.                     
                                                                               
Its wholly-owned subsidiary undertaking Baillie Gifford & Co Limited [1234127; 
0.3%] is an OEIC Authorised Corporate Director and Unit Trust Manager which has
delegated its discretionary investment management role to Baillie Gifford & Co.
                                                                               
Its wholly-owned subsidiary undertaking Baillie Gifford Life Limited [6418255; 
1.3%] is a life assurance company which procures discretionary investment      
management services from Baillie Gifford & Co in respect of its own account    
shareholdings.                                                                 

Proxy Voting:                                                                  
                                                                               
10. Name of proxy holder:               N/A                                    
                                                                               
11. Number of voting rights proxy                                              
holder will cease to hold:                                                     
                                                                               
12. Date on which proxy holder will                                            
cease to hold voting rights:                                                   

13. Additional information:             Serco Group plc is disclosing this     
                                        information in accordance with DTR     
                                        5.8.12.                                
                                                                               
14 Contact name:                        Chris Winters, Assistant Company       
                                        Secretary                              
                                                                               
                                        Serco Group plc                        
                                                                               
15. Contact telephone number:           01256 744108