The Informatics for Integrating Biology and the Bedside (i2b2) is one of the sponsored initiatives of the NIH Roadmap National Centers for Biomedical Computing (http://www.bisti.nih.gov/ncbc/). One of the goals of i2b2 is to provide clinical investigators broadly with the software tools necessary to collect and manage project-related clinical research data in the genomics age as a cohesive entity, a software suite to construct and manage the modern clinical research chart. The i2b2 "hive" is a set of software modules called "cells" that have a common messaging protocol that allow them to interact using web services and XML messages. Each cell can be developed by independent investigators to achieve specific analytic goals, and then be integrated into the hive to enhance the functionality available in the i2b2 Hive. We have applied this architecture through several ongoing clinical studies and found it to be of high value. The current version of this software has been released into the public domain and is available at the URL-http://www.i2b2.org.