Thank you Santiago. Here is the exact syntax I used: Note: I'm only posting for clarity for Powershell rookies like me. I have no idea if this exact syntax changes from what Santiago gave me. I wager they both work.

Import-Module Activedirectory

$Attribcsv=Import-csv "C:\Temp\ADUsers_BulkEdit.csv"

ForEach ($User in $Attribcsv)

{

Get-ADUser -Identity $User.samAccountName | set-ADUser -replace @{costCenter=$($User.costCenter)}

}