MathChallenges is the collaboration of two
long-term fans of recreational mathematics:

Author, teacher, consultant Theoni Pappas is dedicated to sharing her passion about mathematics.  She has written a remarkable series of innovative math books which reflect her commitment to demystifying mathematics and making the subject more approachable.  Her math calendars and over 15 math books appeal to both young and adult audiences and intrigue the "I hate math people" as well as math enthusiasts.  She received the Excellence in Achievement Award  from the University of California Alumni Association for her contributions of books and other innovative products that deal with mathematics. A native Californian, Pappas received a B.A. degree from the University of California, Berkeley and an M.A. from Stanford University. 

More information about her many publications may be found at the publisher's website:

Dale Lindley is a retired engineer with a life-long interest in the practical and recreational aspects of mathematics.  A California native, he earned a B.S. from the University of California, Berkeley, an M.S. from Santa Clara University, and certificates from executive management programs at MIT and Stanford Universities.  His career spans such diverse activities as the Apollo moon landing, digital encryption technologies, specialized super computers, teaching graduate level courses in field theory and acting as Director of a 500 engineer organization for a major Silicon Valley firm.