The OpenECG Network (www.openecg.net) has been created to promote interoperability in electrocardiography with tutorials, specifications, open source tools, data sets, converters, and interoperability testing. ECG vendors, members of professional organizations, researchers, and other stakeholders participate in the OpenECG network to exchange views and receive assistance in implementation. In 2006, members are more than 700 individuals from 58 countries. A specific focus area for OpenECG that concerns diagnostic quality resting electrocardiograms (ECGs) is SCP-ECG, the European standard (EN1064:2005). An online interoperability testing service assists members in consistently implementing SCP-ECG and effortlessly integrating electrocardiographs with eHealth systems. OpenECG is a case of best practice in interoperability that should be followed by medical devices and sensors for effective personalized health monitoring.