Porous liquids are a counter-intuitive new class of porous material consisting of a liquid with permanent, empty holes. They are unique in that they combine the fluidity of liquids with the porous properties of solids. This means that they can absorb large amounts of guest molecules, such as gases, into the holes, but also have the ability to flow. Therefore, they could have future potential in applications such as carbon capture. We have recently reported the first examples of porous liquids, but in order to design the next generation and find applications for these systems, we need to gain an understanding of their structure and how potential guests behave in the liquids. The in-depth study that we will perform will provide us with this information, and will help us gain a detailed understanding of their properties and aid the design of the next generation of these new materials.