  These notes provide an overview of Fixed-Field Alternating-Gradient (FFAG)
accelerators for medical applications. We begin with a review of the basic
principles of this type of accelerator, including the scaling and non-scaling
types, highlighting beam dynamics issues that are of relevance to hadron ac-
celerators. The potential of FFAG accelerators in the field of hadron therapy
is discussed in detail, including an overview of existing medical FFAG designs.
The options for FFAG treatment gantries are also considered.
