The paper examines the theoretical foundations of a dynamic systems (DS) approach to play in the field of Early Childhood Education. It is argued that dynamic systems insight from developmental psychology (van Geert, 2007) and system theory insight from sociology (a Luhmanian perspective is also shortly analysed in regard to play) are able to contribute to an integrative concept of play to better understand preschool practice as well as to make possible effective changes in practice in connection to play. The paper summarises such DS approach features as self-organisation, attractors or phase transition in connection to play. The links to General System Theory and Cultural Historical Activity Theory (CHAT) are also discussed. DS methodology is associated with measuring and assessing dynamic changes in a defined system. DS method being the most challenging issue within this approach is represented by State Space Grids (SSG) (Hollenstein). The paper analyses possibilities and limitations of SSG as a method for studying play, capturing and measuring its features.The paper is based on secondary data devoted to the DS approach, therefore the main ethical considerations have been made concerning both fair presentation and critical considerations of the presented theoretical approach. Looking at how the concept of play can be defined from a system theory perspective and dynamic systems approach in particular is a starting point of a discussion. Implication of this theoretical approach for the field of Early Childhood Education will be discussed using an example of playing interactions of children-newcomers.