Preface From the Editor-in-Chief.

It is my great pleasure to present to you this special issue of the IEEE TRANSACTIONS ON MAGNETICS containing selected extended papers originally presented at the 20th Conference on the Computation of Electromagnetic Fields (Compumag 2015), which took place in Montreal from June 28 to July 2, 2015. From the original nearly 650 papers submitted to Compumag Montreal, 423 were presented at the conference and 348 submitted in extended format to the IEEE TRANSACTIONS ON MAGNETICS. Of those, 231 have been accepted and are included in this issue. [ABSTRACT FROM AUTHOR]