This collection of papers will address the question "What is the Magnetospheric Cusp?" and what is its role in the coupling of the solar wind to the magnetosphere as well as its role in the processes of particle transport and energization within the magnetosphere. The cusps have traditionally been described as narrow funnel-shaped regions that provide a focus of the Chapman-Ferraro currents that flow on the magnetopause, a boundary between the cavity dominated by the geomagnetic field (i.e., the magnetosphere) and the external region of the interplanetary medium. Measurements from a number of...

Rei?, David G. Sibeck, George L. Siscoe, J. David Winningham, Joachim Woch, Masatoshi Yamauchi, Andrew W. Yau, and Qiugang Zong The editors of this special issue express deep gratitude to the Managing Editor of Surveys in Geophysics, Dr. Michael Rycroft, for his support during the project, which was above and beyond the call of duty, and for his careful reading and his insightful comments on each of the papers published in this issue. Guest Editors THEODORE A. FRITZ Center for Space Physics Boston University Boston, MA 02215 USA SHING F. FUNG Space Physics Data Facility NASA Goddard Space...