Rock glaciers, a key element of alpine mountain geomorphic systems, consist of coarse surface debris that insulates an ice-core or ice-debris mixture. Rates of movement of rock glaciers vary from 1 to 100 cm yr-1. Rock glaciers exist in mainly continental dry climates in areas that have high rates of talus accumulation. New geospatial techniques, high-resolution data sources, and improved technology will contribute to a better understanding of these features on Earth and perhaps on Mars. This chapter provides an in-depth summary of important research findings pertaining to rock glaciers and offers insight to future research. 2013 Elsevier Inc. All rights reserved.