I will present a multiscale modeling approach used for predicting mechanical responses of nacre-mother-of-pearl. Nacre is a laminated, segmented, hybrid nanocomposite incorporating 10-20 nm-thick organic matrix film that surrounds 250 nm-thick aragonitic CaCO3 pseudo-hexagonal platelets that are staggered across layers, a brick-mortar nanoarchitecture. Bulk mechanical properties (strength, toughness, controlled failure) of nacre are orders of magnitude better than most advanced ceramics and synthetic ceramic/polymer composites. Many mollusk species, e.g., cephalopods, bivalves, and gastropods, have nacre structure that has survived millions of years of evolution. Our model incorporates details of nano- and micro-structural characteristics including aragonite crystallography and morphology determined by TEM. TEM EELS results indicate difference in electronic properties of geological aragonite and that found in nacre. As mechanical parameters, we use local properties of the individual components, biogenic aragonite and the organic matrix, measured by nanoindentation technique via an atomic force microscope. Using this finite element analysis-based model, we can now predict bulk properties of nacre. For example, our numerical simulations indicate that the organic layer, a molecular composite of polysaccharides and proteins, is a material of high yield strength and elastic modulus, orders of magnitude higher than those of synthetic polymers. Several details of nanoarchitecture, such as influence of inorganic-inorganic nanosized contacts through the organic layer on bulk properties of nacre are quantitatively related to response of nacre under loading. Our model may have significant implications in biomimetic design of layered hybrid nanocomposites for practical engineering applications as wear resistant, impact resistant, tough, and durable materials.