Currently, the media consumption paradigm is changing from a single end user to a group shared experience. Now, social communication opportunities may be exploited (e.g., conferencing while watching television), facing lots of technological (e.g., synchronization, universal session handling, scalability) and perceptual (e.g., presence awareness, QoE) challenges. This article focuses on one of these major challenges ahead in new emerging social interactive multimedia applications, which is the synchronization of different media streams across multiple locations, known as inter-destination multimedia synchronization (IDMS). We describe the three kinds of temporal multimedia synchronization, and summarize some related work and examples of applications in which IDMS is needed. The article includes a discussion about an RTP/RTCP-based IDMS solution the authors have been working on, as well as the standardization status regarding this kind of synchronization.