+3  A: 

Looks like there is no solution to this problem. The bug is aknowleged by microsoft, but its still not fixed in SSRS2008.

From the KB article (http://support.microsoft.com/kb/938943)

This behavior occurs because the Subreport control has an implicit KeepTogether property. By design, the KeepTogether property tries to keep content of a subreport on one page. Because of this behavior, the report engine creates blank space on the main report if the subreport does not fit on the same page as the main report. Then, the report engine creates the subreport on a new page.

The work around that they list is essentially 'don't use subreports'

Nathan Reed
Thanks for pointing me toward the article. I guess I'll just have to do what I can and hope a fix comes out. I have a dynamic report builder that users use to create the reports, not using sub-reports (while not impossible) is out of the question. It would just take too much re-writing to make it worth the effort.
Dustin Brooks
A: 

Another way I got around this was to place the subreport in the report header. Of course that is very dependent on the report content and elminates any of the usefulness of subsequent sections but it did solve my problem of having a huge chunk of whitespace on the first page.

Ben
A: 

right click of subreport and chose format subreport, then uncheck keep object together

lalo
Doesn't exist in Reporting Services 2005.
Dustin Brooks