Closure is a tool owned and maintained by TomorrowToday. It helps ad-hoc project teams with information work that needs people from more than one team to share facts, answers, and decisions.
Someone opens a case for one piece of that work. Closure asks each invited person on their own schedule and brings the result back to the person who opened the case.
Anyone with an email address can take part when someone on the case invites them. There is nothing to install and no password. Closure emails a sign-in code. The invite is what lets them in.
A case is opened for one of these, and Closure coordinates the people involved until that piece of work is settled.
Other mixed coordination can still be a case, such as confirming a name, collecting a file, and getting a fact from three different people.
After the case closes, Closure deletes what it stored for that work. The usual keep time is 60 days after the coordination ends. The person who opened the case can choose a shorter time. TomorrowToday sets the longest time an owner may ask for. The owner is told before a case is deleted.