This thesis argues that in order to understand contemporary media artworks that use and address data, we need to develop what I term a ‘relational understanding’ of data. This can be achieved by challenging common assumptions of data as somehow being ‘pure’, ‘raw’, or taken as a given. For this thesis, data is not considered as a pre-existing instantiated object (as is the case in object-oriented programming for instance). Instead, I consider the complex and relational nature of data—both as it emerges from human systems, and as it produces those systems. Through a creative-practice-as-research approach, this thesis moves beyond the idea that there is such a thing as “raw” data, and advances the novel idea of “data as ecology”. This thesis articulates the complex network of relations that make, shape and create media artworks. At its core, this involves exploring the materiality of data. In order to better understand this, I analyse the processes that bring data into existence, and conduct an investigation into the more precise nature of the interconnections that the world of data both creates and puts into action. In this thesis, ecologies of both practice and media are explored in order to propose a working model of “data ecologies”. This is established by means of a number of original interactive, reactive, and generative new-media works that have been made and exhibited during the course of this investigation. I consider this original creative practice within the broader field of investigation and against the backdrop of a wider body of creative works that have been made by artists over the past decade. To advance this analysis of how data ecologies perform across these clearly delineated fields, I review and assess a number of key media artworks (including my own original creative practice components made during the course of this research, specifically, Laika’s Dérive and Hothouse). The data ecologies that this thesis outlines and analyses enable a new productive approach for media art practices to attend to the processual quality of data in a novel ecological framework that can be used to communicate complex poetic knowledge systems.