The information in healthcare institutions is generally managed by computer applications deployed in medical centers. Usually, each organization has its own system, which is normally proprietary and makes it difficult the exchange of information with other institutions. This chapter discusses the use of mobile agent technology [51,7] as an enabler of open distributed eHealth applications. More precisely, it describes some successful experiences based on this technology: one regarding integration of medical information, and two concerning emergency scenarios. These three successful cases can be very useful at the time of designing new eHealth systems since they have already solved many of the most common issues in this domain. © 2010 Springer-Verlag Berlin Heidelberg.