Hourcade, Juan PabloBederson, Benjamin B.A major difficulty in writing Single Display Groupware (co-present collaborative) applications is getting input from multiple devices. We introduce MID, a Java package that addresses this problem and offers an architecture to access advanced events through Java. In this paper, we describe the features, architecture and limitations of MID. We also briefly describe an application that uses MID to get input from multiple mice: KidPad. Also cross-referenced as UMIACS-TR-99-26en-USTechnical Report