This book is a timely collection of nine papers concerned with the emplacement of silicic domes and mafic lava flows. The authors have utilized a combination of field, experimental, and theoretical methods to constrain various characteristics of recently-emplaced lavas, including dimensions, growth rates, surface morphology, deformation styles, rheology, and volatile contents. The studies take advantage of new, detailed field measurements from numerous volcanoes, with an emphasis on data from Mount St. Helens. Such investigations will be of value to geologists responsible for evaluating hazards, geothermal resources, and volcanogenic ore deposits. They will also be of interest to planetary geologists involved in the remote interpretation of volcanic products and petrologists assessing the rheology of magmas.