Mathematical Methods for Partial Differential Equations is an introduction in the use of various mathematical methods needed for solving linear partial differential equations. The material is suitable for a two semester course in partial differential equations for mathematicians, engineers, physicists, chemistry and science majors and is suitable for upper level college undergraduates or beginning graduate students. Chapter one reviews necessary background material from the subject area of ordinary differential equations and then develops solution techniques for some easy to solve partial differential equations. Chapter two introduces orthogonal functions and Sturm-Liouville systems. Chapter three utilizes orthogonal functions to develop Fourier series and Fourier integrals. The fourth, fifth and sixth chapters consider various applied engineering applications of partial differential equations. Selected applied topics are developed together with necessary solution methods associated with parabolic, hyperbolic and elliptic type partial differential equations. Chapter seven introduces transform methods for solving linear partial differential equations. Numerous examples associated with the Laplace, Fourier exponential, Fourier sine, Fourier cosine and selected finite Sturm-Liouville transforms are given. Chapter eight introduces Green's functions for ordinary differential equations and chapter nine finishes with applications of Green function techniques for solving linear partial differential equations. There are four Appendices. The Appendix A contains units of measurements from the Système International d'Unitès along with some selected physical constants. The Appendix B contains solutions to selected exercises. The Appendix C lists mathematicians whose research has contributed to the area of partial differential equations. The Appendix D contains a short listing of integrals. The text has numerous illustrative worked examples and over 340 exercises.