This is the first systematic and self-contained textbook on homotopy methods in the study of periodic points of a map. A modern exposition of the classical topological fixed-point theory with a complete set of all the necessary notions as well as new proofs of the Lefschetz-Hopf and Wecken theorems are included. Periodic points are studied through the use of Lefschetz numbers of iterations of a map and Nielsen-Jiang periodic numbers related to the Nielsen numbers of iterations of this map. Wecken theorem for periodic points is then discussed in the second half of the book and several results on the homotopy minimal periods are given as applications, e.g. a homotopy version of the Åarkovsky theorem, a dynamics of equivariant maps, and a relation to the topological entropy. Students and researchers in fixed point theory, dynamical systems, and algebraic topology will find this text invaluable.