The William Bowie Medal, for outstanding contributions to fundamental geophysics and for unselfish cooperation in research, is awarded to Hannes Alfven (University of California, San Diego). Alfven has made basic contributions to plasma physics, space physics, and astrophysics. Among these are the discovery of electromagnetic waves, now called Alfven waves, the development of the concept of electric fields in space, and identification of the critical ionization process. He is known for his generosity with his ideas and time, with everyone from undergraduates to heads of state. Alfven's accomplishments were recognized with the 1970 Nobel Prize for Physics.