Start a discussion
When an ad hoc topic needs to be discussed which does not require the entire team to get involved you can always start a discussion with members, guests you invite to a discussion.
All you need to do is click on the Add discussion button.
Type the discussion topic and hit "Add Discussion"
Invite members guests to the discussion just like you would in a team.
For example if a discussion is started on a topic for Event Banners
Then you get an option to add discussion members with you as the Admin of the discussion
And then you can invite members and guests
Then just click on Go to messages continue messaging in this context.
Start messaging here