Last year, Google implemented a change to Hangouts that allows your team to opt-in to a chat, rather than having to invite people one by one. Now Google is improving how you create group chats for projects or teams. You can name your group chats more easily when creating them. Once the group chat has a name, you can create "placeholder" group chats which can be shared with a link.
These improvements will be available in all three Hangouts user interfaces on the web. In Hangouts in Gmail, a "+" button will be next to the contacts list in Hangouts. In hangouts.google.com and in the Chrome extension, you will see a "New conversation" option. By clicking "New group" or "New conversation" you can name the group or start adding members.