Cadherin-catenin adhesion is pivotal for the development of multicellular organisms. Features such as a large repertoire of homotypically interacting cadherins, rapid assembly and disassembly, and a connection to a force-generating actin cytoskeleton make cadherin-mediated junctions ideal structures for the execution of complex changes in cell and tissue morphology during development. Recent findings highlight the role of cadherin-catenin proteins as critical regulators of major developmental pathways. We re-evaluate the significance of cadherin-catenin adhesion structures and propose that in addition to intercellular adhesion, they may be used as biosensors of the external cellular environment that help adjust the behavior of individual cells to ensure survival of the entire organism.