Exhibit 12.1

Advanstar Communications 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 |                                      | $       | (27,172   | )     
|                                                                             | Portion of rents representative of interest factor                          |                                      |         | 1,368     |       
|                                                                             | Interest on indebtedness                                                    |                                      |         | 27,862    |       
|                                                                             |                                                                             |                                      |         |           |       
|                                                                             |                                                                             | Earnings (loss) before fixed charges |         |           | 2,058 
|                                                                             |                                                                             |                                      |         |           |       
|Fixed charges:                                                               |                                                                             |                                      |         |           |       
|                                                                             | Portion of rents representative of interest factor                          |                                      |         | 1,368     |       
|                                                                             | Interest on indebtedness                                                    |                                      |         | 27,862    |       
|                                                                             |                                                                             |                                      |         |           |       
|                                                                             |                                                                             | Total fixed charges                  |         |           | 29,230
|                                                                             |                                                                             |                                      |         |           |       
|Ratio of earnings to fixed charges                                           |                                                                             |                                      |        |           |       
|                                                                             |                                                                             |                                      |         |           |       
|Deficiency in the coverage of fixed charges by earnings before fixed charges |                                                                             | $                                    | (27,172 | )         | $     
|                                                                             |                                                                             |                                      |         |           |       

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|                                                         |                             | Predecessor |         | Advanstar |  
|-------------------------------------------------------- | --------------------------- | ----------- | ------- | --------- | -
|
|
|
|
|Income Statement Data:                                   |                             |             |         |           |  
|Net Revenue                                              |                             | $           | 259,825 |           | $
|Cost of production and selling                           |                             |             | 174,575 |           |  
|General and administrative expenses                      |                             |             | 27,454  |           |  
|Stock option compensation expense (benefit) (1)          |                             |             | 3,397   |           |  
|Funding of affiliated dot.com company operations         |                             |             |        |           |  
|Depreciation and amortization (2)                        |                             |             | 51,823  |           |  
|                                                         |                             |             |         |           |  
|Operating income (loss)                                  |                             |             | 2,576   |           |  
|Other income (expense):                                  |                             |             |         |           |  
|                                                         | Interest expense            |             |         | (27,862   | )
|                                                         | Other income (expense), net |             |         | (1,926    | )
|                                                         |                             |             |         |           |  
|Income (loss) before income taxes and minority interests |                             |             | (27,212 | )         |  
|Provision (benefit) for income taxes                     |                             |             | 1,264   |           |  
|Minority interests                                       |                             |             | 40      |           |  
|                                                         |                             |             |         |           |  
|Income (loss) from continuing operations                 |                             | $           | (28,436 | )         | $
|                                                         |                             |             |         |           |  
|Cash flows provided by (used in):                        |                             |             |         |           |  
|                                                         | Operating activities        |             | $       | 33,568    |  
|                                                         | Investing activities        |             |         | (358,261  | )
|                                                         | Financing activities        |             |         | 332,600   |  
|Balance sheet data (at end of period):                   |                             |             |         |           |  
|Cash and cash equivalents                                |                             | $           | 14,016  |           | $
|Working capital (3)                                      |                             |             | (33,232 | )         |  
|Total assets                                             |                             |             | 660,226 |           |  
|Total debt                                               |                             |             | 426,868 |           |  
|Total stockholder's equity                               |                             |             | 134,760 |           |  
|Other Data:                                              |                             |             |         |           |  
|EBITDA (4)                                               |                             | $           | 53,828  |           | $
|Adjusted EBITDA (4)                                      |                             |             | 57,225  |           |  
|Capital expenditures                                     |                             | $           | 4,154   |           | $
|Ratio of earnings to fixed charges (5)                   |                             |             |        |           |  

2

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|                                                  |  | Predecessor |         | Advanstar |  
|------------------------------------------------- |  | ----------- | ------- | --------- | -
|
|
|
|
|Reported income (loss) from continuing operations |  | $           | (28,436 | )         | $
|Add: goodwill amortization, net of tax            |  |             | 25,099  |           |  
|                                                  |  |             |         |           |  
|Adjusted income (loss) from continuing operations |  | $           | (3,337  | )         | $
|                                                  |  |             |         |           |  

|                                                                 |  | Predecessor |        | Advanstar |  
|---------------------------------------------------------------- |  | ----------- | ------ | --------- | -
|
|
|
|
|Operating income (loss)                                          |  | $           | 2,576  |           | $
|Depreciation and amortization                                    |  |             | 51,823 |           |  
|Minority interests (excluding depreciation and amortization)     |  |             | (571   | )         |  
|                                                                 |  |             |        |           |  
|EBITDA                                                           |  |             | 53,828 |           |  
|                                                                 |  |             |        |           |  
|Stock option compensation expense                                |  |             | 3,397  |           |  
|Provision for notes and advances from affiliated dot.com Company |  |             |       |           |  
|                                                                 |  |             |        |           |  
|Adjusted EBITDA                                                  |  | $           | 57,225 |           | $
|                                                                 |  |             |        |           |  

|                                                             |  | Predecessor |         | Advanstar |  
|------------------------------------------------------------ |  | ----------- | ------- | --------- | -
|
|
|
|
|EBITDA                                                       |  | $           | 53,828  |           | $
|Depreciation and amortization                                |  |             | (51,823 | )         |  
|Minority interests (excluding depreciation and amortization) |  |             | 571     |           |  
|                                                             |  |             |         |           |  
|Operating income (loss)                                      |  |             | 2,576   |           |  
|Interest expense                                             |  |             | (27,862 | )         |  
|Other income (expense),net                                   |  |             | (1,926  | )         |  
|(Benefit) provision for income taxes                         |  |             | 1,264   |           |  
|Minority interests                                           |  |             | 40      |           |  
|Extraordinary item, net of tax                               |  |             |        |           |  

3

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|Cumulative effect of accounting change, net of tax and monority interest |  |  |        |   |  |        |   |  |  |  |  |  |        |   |  | (552    | ) |  | (66,817  | )
|------------------------------------------------------------------------ |  |  | ------- | - |  | ------- | - |  |  |  |  |  | ------- | - |  | ------- | - |  | -------- | -
|                                                                         |  |  |         |   |  |         |   |  |  |  |  |  |         |   | 
|Net Loss                                                                 |  |  | (28,436 | ) |  | (585    | ) |  |  |  |  |  | (18,535 | ) |  | (49,762 | ) |  | (124,339 | )
|Extraordinary item-early extinguishment of debt                          |  |  |         |   |  |         |   |  |  |  |  |  |        |   |  | 2,556   |   |  |         |  
|Provision for notes and advances from affiliataed dot.com company        |  |  |        |   |  |        |   |  |  |  |  |  |        |   |  |        |   |  | 37,192   |  
|Transition goodwill impairment                                           |  |  |        |   |  |        |   |  |  |  |  |  |        |   |  |        |   |  | 66,817   |  
|Depreciation and amortization                                            |  |  | 39,158  |   |  | 53,258  |   |  |  |  |  |  | 55,400  |   |  | 94,261  |   |  | 69,132   |  
|Deferred income taxes                                                    |  |  |        |   |  | (12,631 | ) |  |  |  |  |  | 4,942   |   |  | (13,443 | ) |  | (16,605  | )
|Other non cash items                                                     |  |  | 18,990  |   |  | 4,475   |   |  |  |  |  |  | 5,643   |   |  | 6,388   |   |  | 3,597    |  
|Changes in operating assets and liabilities                              |  |  | 3,856   |   |  | 9,003   |   |  |  |  |  |  | (11,177 | ) |  | 1,813   |   |  | (11,519  | )
|                                                                         |  |  |         |   |  |         |   |  |  |  |  |  |         |   | 
|Net cash proivded by (used in) operating Activities                      |  |  | 33,568  |   |  | 53,520  |   |  |  |  |  |  | 36,273  |   |  | 41.813  |   |  | 24,275   |  
|                                                                         |  |  |         |   |  |         |   |  |  |  |  |  |         |   | 

4

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