Recognition of mathematical notation involves two main components: symbol recognition and symbol-arrangement analysis. Symbol-arrangement analysis is particularly difficult for mathematics, due to the subtle use of space in this notation. We begin with a general discussion of the mathematics-recognition problem. This is followed by a review of existing approaches to mathematics recognition, including syntactic methods, projection-profile cutting, graph rewriting, and procedurallycoded math syntax. A central problem in all recognition approaches is to find a convenient, expressive, and effective method for representing the notational conventions of mathematics.