How to add another document to an existing portfolio

[SLM 0]

I have created a portfolio and found another document I want to add to it.  

Do I have to create another brand new portfolio, or is there a way to take the existing one and add to it? 

Thank you!

[Steven Zakulec 60]

I'm not aware of a way to edit an existing portfolio, but if the files were all PDFs, you can easily select them all and have them opened in Nitro, then Create a new portfolio using the open files, then add the final new file to the new portfolio.  Otherwise, you'd have to recreate it with the new file.