Allegion makes security and access control products for doors — locks, exit devices, door closers, electronic access systems, and related hardware — sold into commercial, institutional, and residential buildings. The company operates through two segments: Americas (~80% of revenue), which covers the U.S., Canada, Mexico, and Latin America, and International (~20% of revenue), which covers Europe and Asia-Pacific with key brands in Western Europe. Core brands include Schlage (residential and commercial U.S.), Von Duprin (exit devices), LCN (door closers), CISA and SimonsVoss (European mechanical and electronic locks), and Stanley Access Technologies (automatic door systems). In commercial and institutional markets, Allegion deploys its own spec writers who work with architects and engineers to get Allegion products written into building designs before projects go to bid — products then flow through specialty distributors and contract hardware dealers. In residential, Allegion sells Schlage locks through home improvement retailers, e-commerce, and homebuilder channels. Revenue is driven by construction activity (nonresidential with a 12–24 month lag), aftermarket replacement, price realization, and a mix shift toward higher-margin electronic products. Allegion also generates recurring revenue through Stanley's service business and SaaS-based access control software. M&A is a core part of the growth model, targeting bolt-ons in mechanical hardware, electronics, and software to expand the portfolio and add recurring revenue streams.