Guest editors' preface: Issue dedicated to Professor Frank Stenger

This issue of the Journal of Complexity is dedicated to Professor Frank Stenger on the occasion of his 65th birthday, which was celebrated during the conference: Optimal Algorithms and Computational Complexity for Numerical Problems, in Salt Lake City, in May 2007. Frank has been a friend, mentor, collaborator and teacher for the four of us and for many others. This special issue contains selected papers from the conference and is given in appreciation of all that Frank has done for us and for the field of numerical computation. For over 35 years, Frank has been a crucial researcher in numerical analysis. He was selected by SIAMas one of the fifteenmost influential numerical analysts of theXX century. He founded the field of Sinc methods in numerical computation, authored a Sinc monograph, a numerical analysis textbook, co-authored a monograph on modern computational approximation techniques as well as developed a library of Sinc algorithms, the Sinc–Pack Matlab toolbox. He has published some 150 journal papers ranging overmany areas of engineering and science,mostly in subjects related to computation. He has lectured at universities in 21 different countries. He received the First Degree Prize of the Secretary of Education of Poland in 1996 (jointly with M. Kowalski and K. Sikorski). Frank was born in Hungary. After World War II, he lived in East Germany, then in West Germany, then in Canada, then, after completion of his course studies, in the United States. He claims to have