Exhibit 16.1
September 4, 2009
| Audit • Tax • Advisory | |
| Grant Thornton LLP | |
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RE: Quality Systems, Inc.
File No. 001-12537
Dear Sir or Madam:
We have read Item 4.01 of Form 8-K of Quality Systems, Inc. dated September 4, 2009 and agree with statements concerning our Firm contained therein.
Very truly yours,
/s/ Grant Thornton LLP
Grant Thornton LLP
U.S. member firm of Grant Thornton International Ltd