Exhibit 12.1

Advanstar, Inc.    Computation of Ratio of Earnings to Fixed Charges/Deficiency  in the Coverage of Fixed Charges by Earnings Before Fixed Charges

|                                                                             |                                                                             | Predecessor                          |        | Advanstar |       
|---------------------------------------------------------------------------- | --------------------------------------------------------------------------- | ------------------------------------ | ------ | --------- | ------
|
|
|
|
|Earnings before fixed charges:                                               |                                                                             |                                      |        |           |       
|                                                                             | Income (loss) before income taxes, extraordinary item and accounting change |                                      | $      | (8,312    | )     
|                                                                             | Portion of rents representative of interest factor                          |                                      |        | 1,024     |       
|                                                                             | Interest on indebtedness                                                    |                                      |        | 15,117    |       
|                                                                             |                                                                             |                                      |        |           |       
|                                                                             |                                                                             | Earnings (loss) before fixed charges |        | $         | 7,829 
|                                                                             |                                                                             |                                      |        |           |       
|Fixed charges:                                                               |                                                                             |                                      |        |           |       
|                                                                             | Portion of rents representative of interest factor                          |                                      | $      | 1,024     |       
|                                                                             | Interest on indebtedness                                                    |                                      |        | 15,117    |       
|                                                                             |                                                                             |                                      |        |           |       
|                                                                             |                                                                             | Total fixed charges                  |        | $         | 16,141
|                                                                             |                                                                             |                                      |        |           |       
|Ratio of earnings to fixed charges                                           |                                                                             |                                      |       |           |       
|                                                                             |                                                                             |                                      |        |           |       
|Deficiency in the coverage of fixed charges by earnings before fixed charges |                                                                             |                                      | (8,312 | )         |       
|                                                                             |                                                                             |                                      |        |           |       

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