We describe the development of an abbreviated version of the Test of Functional Health Literacy in Adults (TOFHLA) to measure patients' ability to read and understand health-related materials. The TOFHLA was reduced from 17 Numeracy items and 3 prose passages to 4 Numeracy items and 2 prose passages (S-TOFHLA). The maximum time for administration was reduced from 22 minutes to 12. In a group of 211 patients given the S-TOFHLA, Cronbach's alpha was 0.68 for the 4 Numeracy items and 0.97 for the 36 items in the 2 prose passages. The correlation (Spearman) between the S-TOFHLA and the Rapid Estimate of Adult Literacy in Medicine (REALM) was 0.80, although there were important disagreements between the two tests. The S-TOFHLA is a practical measure of functional health literacy with good reliability and validity that can be used by health educators to identify individuals who require special assistance to achieve learning goals.