Recent work suggests autistic children are impaired in their symbolic (or pretend) play. However, such studies have either used inadequate definitions of ‘pretend’, or have not examined spontaneous play. An experiment is reported which attempts to overcome these difficulties This confirms that autistic children are severely impaired in their ability to produce pretend play, in contrast to non-autistic retarded and normal controls. This is discussed in terms of the symbolic deficit theory (Ricks & Wing, 1975). It is argued that when a ‘symbol’ is defined as being a ‘second-order representation’, this theory has the potential to link both the social and pretend impairments in autism. The theory awaits more adequate testing.