A series aimed at researchers in motor development which includes traditional and experimental approaches and suggests that a transition may be occurring in motor development research. Twelve reports cover such topics as motor skills and sociocultural and methodological considerations. The primary purpose of the series, of which the present publication is the inaugural volume, is to supplement and support journals and annual reviews which report on similar topics. The editors recognize that motor development has evolved into a complex field which cuts across biological, behavioural, biomechanical and other subjects.