The chapter describes an experimental study of the acquisition of derivational diminutives in Hebrew. The study population consisted of 48 children in four age groups: 5–6, 7–8, 10–11, 12–13, and adults. Participants were administered two tasks: an explanation task, and a production task. The learning curves we uncovered begin in kindergarten, with less than one quarter correct productions and about one third correct explanations, and they rise steadily from age 7–8 throughout grade school, especially between ages 9–12. Only from age 12 do Hebrew speakers show that they have mastered the morphological, semantic, pragmatic, and cognitive factors that interact in understanding and producing diminutive forms. Diminutive derivational morphology is thus part of what is termed ‘later language development’, that is, linguistic acquisition during the school years.