The aim of this study was to gain insight into the extent to which health education text writers apply writing principles derived from cognitive psychological theory. Seventeen professional text writers of health education materials participated in a qualitative study, consisting of a rewriting task combined with a think-aloud procedure and a semistructured interview. The verbal data were explored carefully in light of seven text coherence principles that have proven effective in cognitive psychological research to increase text comprehension. Findings indicate text writers vary in their ideas and use of coherence principles to make a text comprehensible. It is argued that the health education profession can benefit greatly from knowledge about cognitive text processing and cognitive coherence principles for realizing effective comprehension of written health education messages. (Contains 2 tables and 1 figure.)