Mobility, a property of Pavlovian higher nervous activity, was measured using an induction task. Negative induction, following presentation of an excitatory stimulus, is an index of mobility of excitation and positive induction, following presentation of an inhibitory stimulus is an index of mobility of inhibition. Mobility scores from 27 male and 37 female first-year psychology students, age 17 to 42 years were related to extraversion and neuroticism derived from Eysenck's Personality Inventory (Form A). Mobility of excitation and mobility of inhibition were found to be unrelated. Individual differences in the magnitude and latency of induction indicate that individuals can be typed according to low, medium, or high mobility of either nervous process. No relationship was found between neuroticism and mobility, and no relationship was found between extraversion and mobility of excitation. However, a significant negative relationship was found between extraversion and mobility of inhibition, providing a link between Pavlovian properties of the nervous system and Eysenck's personality dimension of extraversion.