Identifies a number of fundamental principles of physics which are involved in applying electromagnetic suspensions to transport. The theory relating to these is developed and typical values are given for important variables and parameters when an overall view of the transport system is taken. A number of simplifications and assumptions are used in order to treat as concisely as possible the important considerations. The control of the electromagnets is considered. Electromagnetic suspension systems are an intriguing area of technology. They combine the properties of magnetic fields with advanced control theory; they incorporate advanced instrumentation and state-of-the-art power semiconductors; they bring together the expertise of electrical electronic, mechanical and civil engineers; and they offer a challenge to the long established technology of wheeled systems.