Get Person object then add a value to a multi-value column in One Identity

I have a process I need to write that's going to need a VB script. I have a custom multivalue column on the Person object. When the process fires, I want to add a value to the multivalue column. What would the VB Script look like that would grab the Person object then add a value to a multivalue column without removing the current values that are already in there? Using v8.1.1 if that matters.