In seismic retrofitting of concrete buildings, frame bays are converted to reinforced concrete (RC) walls by infilling the space between the frame members with RC of a thickness of not more than their width. The cyclic behavior of the resulting wall depends on the connection between the RC infill and the surrounding RC members. The paper uses results from 48 cyclic tests of such composite walls to express their properties in terms of the geometry, the reinforcement and the connection. Properties addressed are: a) the yield moment at the story base; b) the secant-to-yield-point stiffness over the shear span of the wall in a story; c) the deflection at flexural failure in cyclic loading; d) the cyclic shear resistance, including sliding shear. Separate models are given for squat walls failing in shear. The models are modifications of the ones developed in the past for monolithic RC walls from several hundred cyclic tests.