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) from continuing operations before income taxes, and cumulative effect of accounting change |                                      | $      | (9,122    | )     
|                                                                             | Portion of rents representative of interest factor                                                       |                                      |        | 1,821     |       
|                                                                             | Interest on indebtedness                                                                                 |                                      |        | 37,858    |       
|                                                                             |                                                                                                          |                                      |        |           |       
|                                                                             |                                                                                                          | Earnings (loss) before fixed charges |        |           | 30,557
|                                                                             |                                                                                                          |                                      |        |           |       
|Fixed charges:                                                               |                                                                                                          |                                      |        |           |       
|                                                                             | Portion of rents representative of interest factor                                                       |                                      |        | 1,821     |       
|                                                                             | Interest on indebtedness                                                                                 |                                      |        | 37,858    |       
|                                                                             |                                                                                                          |                                      |        |           |       
|                                                                             |                                                                                                          | Total fixed charges                  |        |           | 39,679
|                                                                             |                                                                                                          |                                      |        |           |       
|Ratio of earnings to fixed charges                                           |                                                                                                          |                                      |       |           |       
|                                                                             |                                                                                                          |                                      |        |           |       
|Deficiency in the coverage of fixed charges by earnings before fixed charges |                                                                                                          |                                      | (9,122 | )         | $     
|                                                                             |                                                                                                          |                                      |        |           |       

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