Health literacy is receiving national attention as the impact of inadequate health literacy on outcomes is increasingly recognized. Assessment tools exist for identifying patients with inadequate health literacy, but there are difficulties and controversies for use of these measures in clinical practice. Three screening questions for health literacy are typically effective, and "red flags" also help in identifying patients. Patient education materials should be assessed for attributes, readability, and suitability. An action plan to address health literacy in ambulatory care settings is presented.