Investigated age and sex differences in sensation seeking behavior against the background of need theory. A representative population sample was assembled in Germany, comprised of 2,339 respondents (aged 14-79 years). The German version of the Need Inventory of Sensation Seeking (NISS) was administered to each subject. The NISS is composed of two subscales that independently measure need for stimulation and avoidance of rest. The instrument does not contain items that are directly descriptive of concrete sensation seeking behaviors. Multivariate analyses of variance revealed main effects for both sex and age, but no sex-age interaction effects. Overall, sensation-seeking tendencies diminished over the lifespan, and males generally scored higher on the indices of sensation seeking. The findings suggest that the age-specific decline in sensation seeking is independent of specific behavior styles or temperamental traits, and is instead rooted in a more fundamental decrease in an underlying need for stimulation.