2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/64064We propose a notion of operator monotonicity for functions of several variables, which extends the well known notion of operator monotonicity for functions of only one variable. The notion is chosen such that a fundamental relationship between operator convexity and operator monotonicity for functions of one variable is extended also to functions of several variables.Operator AlgebrasRings and Algebras47A56; 26B25; 47A63text