EXHIBIT 23

            CONSENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

The Board of Directors
VASCO Data Security International, Inc.:

We consent to the incorporation by reference in the registration statements on
Form S-8 (No. 333-62829), on Form S-3 (333-46256) and on Form S-1 (333-124458)
of VASCO Data Security International, Inc. and subsidiaries of our reports dated
March 15, 2007, with respect to the consolidated balance sheets of VASCO Data
Security International, Inc. and subsidiaries as of December 31, 2006 and 2005,
and the related consolidated statements of operations, comprehensive income,
stockholders' equity, and cash flows for each of the years in the three-year
period ended December 31, 2006, and the related financial statement schedule,
management's assessment of the effectiveness of internal control over financial
reporting as of December 31, 2006 and the effectiveness of internal control over
financial reporting as of December 31, 2006, which reports are included in the
December 31, 2006 annual report on Form 10-K of VASCO Data Security
International, Inc.

Our report on the consolidated financial statements refers to the Company's
adoption of the provisions of Statement of Financial Accounting Standards No.
123R, Share-Based Payment, modifying share-based compensation in 2006.


                                        /s/ KPMG LLP

Chicago, Illinois
March 15, 2007