I have one table called Primers, whose primary key is PrimerName. I have designed to forms, FormA =PrimerF1 and FormB =SUMMARY. The user inputs information into formA creating records for each primer. The SUMMARY form has a list box with a field referred to as Primer 1 Name. Once the user selects a primer, I would like selected information (sequence, Alias primer name, and location) to show up based upon the primer name selected.

Make the RowSource of the Summary List box something similar to this:
"Select sequence, Alias primer name, location from [YourTable] where PrimerName = Forms![FormA].[PrimerName]"

Using the Form Location is the important part here.

Next on the AfterUpdate of the PrimerName Field add this:

Forms![FormB].[SummaryListBox].Requery

This will requery the listbox and include the new data.