This document summarizes the role of Notch signaling in intestinal homeostasis and cancer. It discusses: 1) Notch signaling balances intestinal stem cell self-renewal and differentiation, maintaining homeostasis of the intestinal epithelium. 2) In the intestine, stem cells in the crypts fuel continuous production of differentiated cell types that move up the villi. Notch signaling controls this process. 3) Dysregulation of Notch is involved in intestinal cancer, as it controls lateral inhibition between stem cells and their differentiation.