This study seeks to gain a baseline understanding of the communication network structure, content of communication, and outcomes in a medical intensive care unit experiencing higher-than- expected central line blood stream infection (CLBSI) rates. The communication network structure refers to the direction and frequency of communication on evidence-based CLBSI prevention practices across various professional subgroups and hierarchical levels in the unit, including medical faculty, nurses, residents, students, unit managers, and hospital administrators. The content of communication refers to the type of knowledge (ie, tacit vs explicit knowledge) exchanged on CLBSI prevention practices. Outcomes include (1) compliance with CLBSI prevention practices and (2) hospital-acquired CLBSI rates in the unit. Data on communication network structure and content of communication are collected using communication logs completed weekly for 4 weeks, by individual participants in each professional subgroup and hierarchical level. Outcomes are collected weekly through chart (medical record) review. Study results indicate a sparse communication network structure with minimal interaction across professional subgroups and hierarchical levels. They also indicate that primarily explicit knowledge on general infection topics is being exchanged as against tacit knowledge on specific infection prevention practices. Unit outcomes are poor, with the central line bundle score at zero during all 4 weeks. The study represents an original attempt at developing methods for measuring the communication network structure related to evidence-based infection prevention practices at the unit level. It lays a foundation for testing hypotheses related to effective communication network structures for hospital infection prevention in a larger study. More significantly, the study lays a foundation for generating concrete and context-sensitive strategies for organizational learning and improvement in the context of evidence-based practices. Such insight is critical from the perspective of evidence-based health care management.