Virtual worlds for children are becoming increasingly popular, and yet there are few accounts of children's use of these worlds. Young children are spending increasing amounts of time online as technology continues to create significant changes in social and cultural practices in the 21st century. Some of children's online interactions can be categorized as playful in nature; however, play and technology are frequently positioned as oppositional. In this article, I explore the tensions surrounding the relationship between play and technology and relate it to similar discourses concerning the concepts of "real" and "virtual". I then move on to consider the growing popularity of virtual worlds with young children and examine the way in which the worlds have been marketed to children and parents/carers on the basis of their propensity to offer online play in a safe environment. The article provides an overview of two virtual worlds currently targeted at young children and draws on a survey of primary children's use of virtual worlds in order to identify the nature of play in these environments. One hundred and seventy-five children aged 5-11 completed an online survey and 15 took part in group interviews in which their use of virtual worlds was explored. This article focuses on the data relating to 17 children aged from five to seven years who used virtual worlds. Findings indicate that virtual worlds offered these young children a wide range of opportunities for play and that the types of play in which they engaged relate closely to "offline" play. The implications for early years educators are considered. (Contains 6 notes.)