This volume contains papers associated with the conference "Atomic Spectra and Collisions in External Fields II", that took place July 30-31 1987 at Royal Holloway and Beford New College. The first meeting of this name was held at the National Bureau of Standards in Gaithersburg, Maryland in 1984, and, if any tradition can yet be said to have been established in the series, it is that the proceedings be written after the conference. We hope thereby to preserve some impression of the discussions that took place, which in both cases were vigorous and unihibited. Both meetings happen to have convened in proximity to major developments in the field. At the time of the first conference, results of experimental measurements of dielectronic recombination in electron ion beams were beginning to appear. These showed large discrepancies with theoretical calculations, which were attributed to the effects of rather weak electric fields on the highly-excited states that mediate the recombination process. This conjecture gave rise to widespread concern in the plasma physics community that the representation of dielectronic recombination in existing plasma models, in which it plays an important role in energy and ionization balance, might be seriously in error due to neglect of the effects of electric and magnetic fields. The subject of field effects on recombination processes was thus a major focus of the 1984 meeting.

techniques, and raises new issues of physical interpretation as well as possibilities for deepening the theory. (3) Barut contributes a comprehensive review of his own ambitious program in electron theory and quantum electrodynamics. Barut's work is rich with ingenious ideas, and the interest it provokes among other theorists can be seen in the cri tique by Grandy. Cooperstock takes a much different approach to nonlinear field-electron coupling which leads him to conclusions about the size of the electron. (4) Capri and Bandrauk work within the standard framework of quantum electrodynamics. Bandrauk presents a valuable review of his theoretical approach to the striking new photoelectric phenomena in high intensity laser experiments. (5) Jung proposes a theory to merge the ideas of free-free transitions and of scattering chaos, which is becoming increasingly important in the theoretical analysis of nonlinear optical phenomena. For the last half century the properties of electrons have been probed primarily by scattering experiments at ever higher energies. Recently, however, two powerful new experimental techniques have emerged capable of giving alternative experimental views of the electron. We refer to (1) the confinement of single electrons for long term study, and (2) the interaction of electrons with high intensity laser fields. Articles by outstanding practitioners of both techniques are included in Part II of these Proceedings. The precision experiments on trapped electrons by the Washington group quoted above have already led to a Nobel prize for the most accurate measurements of the electron magnetic moment.