In our previous work, we described an electronic health record (EHR) architecture based on Web 2.0 principles. With this architecture, users in healthcare and public health can select, configure, share and control the information and interfaces they use by means of simple techniques such as “drag-and-drop” without the intervention of programmers. We extend this work by discussing architectural and usability considerations important for creating such an EHR. These include: new affordances facilitating element creation, responsiveness while using rich client-side interaction, consistency versus flexibility, security, workflow and evaluation. [ABSTRACT FROM AUTHOR]