Hi, I was trying to use Announcements. In a nutshell I've a spec window which displays a collection of objects that are stored by a manager. By reading the collaborActive book, and the Help menu that comes with Pharo, I managed to have it working but I've a couple of question. Initially I modeled the thing as two separated announcers, one that sends events (i.e., the manager when new objects are added/removed) and another (i.e., the window which sends the on:do: message with the right Announcement subclass to perform something on the window itself). Unfortunately, this procedure did not work since the two announcers did not communicate between themselves. The solution I adopted is that the window (i.e., consumer of events) sends the on:do: message to the announcer of the manager. Is this the desired pattern to follow? Thanks in advance, Roby