This chapter explains what the function of a mortgage as a security interest, and details the different forms of mortgages that now exist. It discusses the rights, remedies, and protections available to the mortgagor and mortgagee, and the process by which the courts have intervened in the contractual relationship largely for the protection of the borrower. Protections available for the homeowner, and for third parties whose rights are affected by a mortgage, are discussed. Finally, the problems of pressure and the law of undue influence are introduced.