EXHIBIT 21.1

SUBSIDIARIES OF SWITCH & DATA FACILITIES COMPANY, INC.



|    |  |                                         |  |                             
|--- |  | --------------------------------------- |  | ----------------------------
|No. |  | Name of Subsidiary                      |  | Jurisdiction of Organization
|    |  |                                        
|1.  |  | Switch & Data Holdings, Inc.            |  | Delaware                    
|    |  |                                        
|2.  |  | Switch and Data Enterprises, Inc.       |  | Delaware                    
|    |  |                                        
|3.  |  | Switch & Data Facilities Company LLC    |  | Delaware                    
|    |  |                                        
|4.  |  | Switch and Data Operating Company LLC   |  | Delaware                    
|    |  |                                        
|5.  |  | Switch and Data Management Company LLC  |  | Delaware                    
|    |  |                                        
|6.  |  | Switch and Data Toronto, Ltd.           |  | Ontario                     
|    |  |                                        
|7.  |  | Switch & Data AZ One LLC                |  | Delaware                    
|    |  |                                        
|8.  |  | Switch & Data CA One LLC                |  | Delaware                    
|    |  |                                        
|9.  |  | Switch & Data CA Two LLC                |  | Delaware                    
|    |  |                                        
|10. |  | Switch and Data CA Nine LLC             |  | Delaware                    
|    |  |                                        
|11. |  | Switch & Data CO One LLC                |  | Delaware                    
|    |  |                                        
|12. |  | Switch & Data FL One LLC                |  | Delaware                    
|    |  |                                        
|13. |  | Switch & Data FL Two LLC                |  | Delaware                    
|    |  |                                        
|14. |  | Switch & Data FL Four LLC               |  | Delaware                    
|    |  |                                        
|15. |  | Switch and Data FL Seven LLC            |  | Texas                       
|    |  |                                        
|16. |  | Switch & Data GA One LLC                |  | Delaware                    
|    |  |                                        
|17. |  | Switch and Data GA Three LLC            |  | Delaware                    
|    |  |                                        
|18. |  | Switch & Data IL One LLC                |  | Delaware                    
|    |  |                                        
|19. |  | Switch & Data IN One LLC                |  | Delaware                    
|    |  |                                        
|20. |  | Switch & Data LA One LLC                |  | Delaware                    
|    |  |                                        
|21. |  | Switch & Data MA One LLC                |  | Delaware                    
|    |  |                                        
|22. |  | Switch & Data MI One LLC                |  | Delaware                    
|    |  |                                        
|23. |  | Switch & Data MO One LLC                |  | Delaware                    
|    |  |                                        
|24. |  | Switch & Data NY One LLC                |  | Delaware                    
|    |  |                                        
|25. |  | Switch and Data NY Four LLC             |  | Delaware                    
|    |  |                                        
|26. |  | Switch and Data NY Five LLC             |  | Delaware                    
|    |  |                                        
|27. |  | Switch & Data/NY Facilities Company LLC |  | Delaware                    
|    |  |                                        
|28. |  | Switch & Data OH One LLC                |  | Delaware                    
|    |  |                                        
|29. |  | Switch & Data PA Two LLC                |  | Delaware                    
|    |  |                                        
|30. |  | Switch and Data PA Three LLC            |  | Delaware                    
|    |  |                                        
|31. |  | Switch and Data PA Four LLC             |  | Delaware                    
|    |  |                                        
|32. |  | Switch & Data TN Two LLC                |  | Delaware                    
|    |  |                                        
|33. |  | Switch & Data TX One LLC                |  | Delaware                    
|    |  |                                        
|34. |  | Switch and Data TX Five LP              |  | Delaware                    
|    |  |                                        
|35. |  | Switch and Data Dallas Holdings I LLC   |  | Delaware                    
|    |  |                                        
|36. |  | Switch and Data Dallas Holdings II LLC  |  | Delaware                    
|    |  |                                        
|37. |  | Switch & Data VA One LLC                |  | Delaware                    
|    |  |                                        
|38. |  | Switch & Data VA Two LLC                |  | Delaware                    
|    |  |                                        
|39. |  | Switch and Data VA Four LLC             |  | Delaware                    
|    |  |                                        
|40. |  | Switch & Data WA One LLC                |  | Delaware                    
|    |  |                                        
|41. |  | Switch and Data WA Three LLC            |  | Delaware                    
|    |  |                                        
|42. |  | Switch and Data CA Eleven LLC           |  | Delaware                    
|    |  |                                        
|43. |  | Switch and Data NJ Two LLC              |  | Delaware