When categorization behaviour is compared between young and elderly adults, results usually show a decrease in taxonomic choices along with an increase in thematic choices. This can be interpreted in two ways: a decline in the ability to perceive and use taxonomic relations, or a modification of conceptual preferences with aging related to a bias stemming from material which favours young adults. We evaluated the second hypothesis by studying whether the salience of categorical associations could explain the differences generally observed between young and elderly adults. This hypothesis was tested on 25 young subjects (M = 45.3 years, SD =5.6 years) and 30 elderly subjects (M = 71.5 years, SD = 7.1 years) using a matching task: individual judgments were used to build triads in which a target was presented along with a strong and a weak associate. In line with our hypothesis, both age groups were influenced by associative strength and type of relation in the same way. Results are interpreted with Baltes's [1987, Developmental Psychology, 23, 611–626] model.