In this text meteorology and the theory of glacier flow are brought together, providing a basic understanding of how glaciers respond to climate change. Attention is given to the microclimate of glaciers and the physical processes that regulate the exchange of energy and mass between glacier surface and atmosphere. Simple analytical and numerical models are used to investigate the sensitivity of glaciers to climate change, to estimate response times, to make an interpretation of historical glacier records, and to assess the contribution of glacier melt to sea-level rise. Modern developments in glacier research, including satellite measurements, are discussed in the final chapter.