Coordinating care for hospitalized patients requires the use of multiple sources of information. Using a macroergonomic framework (i.e. the work system model), we conducted interviews and observations of care managers involved in care coordination across transitions of care. When information is distributed across multiple health IT applications, care managers experience a range of challenges, including organizational barriers, technology design problems, skills and knowledge issues, and task performance demands (i.e. issues related to individual information processing and management and sharing of information). These challenges can be used as a checklist to evaluate the proposed IT infrastructure that will allow the integration of multiple health IT applications and, therefore, support coordination across transitions of care.