This book details state-of-the-art fuel cell systems incorporating methanol reformers as the source of purified hydrogen (rather than compressed hydrogen). Beginning with an overview of PEM fuel cells, the book discusses the various technical approaches to methanol reforming and hydrogen purification. A unique theme that is carried throughout the discussion is the practical aspects of commercial applications that favor one technical approach over another. The reader gains an understanding of the chemistry, engineering, economics, and agency certification requirements that ultimately shape the optimal approach for methanol fuel cell systems targeting commercial applications.