Artificial, layered heterostructures of transition metal oxides provide an opportunity to tune and couple electronic charge and spin properties on an atomic scale. Strong correlations between electrons can then lead to the formation of exotic new phases at the interfaces which are impossible to stabilise in the bulk materials. This proposal describes an experimental project to investigate the LaAlO3-SrTiO3 heterostructure, where a 2-D electron gas (2DEG) is formed at the LaO:TiO2 interface. The project will employ state of the art magnetotransport and magnetometry techniques in high magnetic fields, at low temperatures and at high pressure. By tuning these thermodynamic parameters we will be able to map a comprehensive phase diagram for the interface, and determine many important aspects of the 2DEG behaviour. Further measurement as a function of sample orientation in a magnetic field will allow us to examine the extent and influence of 2-dimensionality in this system, and by varying the sample growth conditions we will study the effects of disorder, and the relevance of the surface to the properties of the interface. Our measurements aim to fully characterise the magnetic and conducting properties of the metallic interface in the LaAlO3-SrTiO3 heterostructure, provide new insight into why and how these remarkable interface phases arise, and identify promising directions for the growth of new structures of fundamental and technological interest. The project will involve collaboration between the Nijmegen High Field Magnet Laboratory (HFML), MESA+ at the University of Twente, and the Physics Department of the University of Toronto. As work proceeds, some advancement and development of measurement techniques and procedures will be necessary. This will extend the capabilities of the Nijmegen HFML, and result in a combination of facilities for EuroMagNET users that is unavailable anywhere else in the world. We consider this to be an important aspect of our proposal