how do I append data to a dataset

Question

I need to have a dataset that appends records of the same TYPE.  
The following line returns a set of data.   How do I add these rows to a master dataset.  If I use dataset.Copy() that I believe overlays previous data.
this.eventDetailUpdater_req = InsertNewDetailEvent(currentIdx);
 

 
while ( currentIdx < this.detailChanges.ResponseRepeatableDataArea.Count)
{
this.eventDetailUpdater_req = InsertNewDetailEvent(currentIdx);
currentIdx += eventDetailUpdater_req.PlanIclDetailArea.Count;
 
//eventDetailUpdater_AllRecords += eventDetailUpdater_req;
 
bStatus = CallHandlerView(eventDetailUpdater_req, response, msg, true);
}