Heather, the Baseline Cost field is a cost field and should default to $0 if not updated. Not sure why some of them are set to Null as I am unable to show Null in either Project 2016 or Project 2010 no matter how the task is setup. Also, when rolling up selected tasks selecting the “to all summary tasks” will roll the cost up through all summary tasks for the selected detail tasks…up to the Project Summary task. So in short, I’m not sure why you are getting nulls in the Baseline Cost field of any tasks. Does it work correctly going forward if you enter a 0 in the field? Is there anything similar about those summary tasks? Any additional information you can think of would be great.