Here's how to invite users in Progression:
Using the left side navigation menu, scroll to your organisation's name β click on 'People' below this
Here you'll see a list of all the People in your organisation
Click 'Invite user'
Add a first and last name, email and position
Choose whether you want to send an invite straightaway β you can do this later by unticking the box
You can also choose whether this user should be an organisation Admin in 'More options'.