The Stroop task, a classic paradigm from experimental psychology, is frequently used in clinical neuropsychology as a tool for testing selective attention, particularly the ability to suppress irrelevant information. The aim of the present study is to collect normative data in the Italian population on an easily-handled paper version of the Stroop test characterized by a unique measure of interference (number of correct items within a time period). One-hundred and sixty healthy adults, well distributed across age (18-77), education and sex, underwent the study. Normative values were calculated following the equivalent score method which permits to compare performance at different neuropsychological tasks.