I believe SSRS lacks the functionality to keep groups of data together.
Say I have a table containin one grouping of data. The report contains enough groups to use more that one 'page' when rendered. The report splits an individual group if it appears at the bottom of the page amd continues with the details on the subsequent page. There seems to be no method of keeping the group together i.e. if the indivual group will not completely fit on the bottom of the page, it will be rendered in its entirety on a fresh page. Thinking about it, if this functionality were available what would happen to a group of data that naturally exceeds one rendered page?
A work-around that may work....keep a tally of the the number of rows returned and insert a page break after x.....will look into this...