Using an approach based on quasiclassical Green's functions we present a theoretical study of transport in mesoscopic SN structures in the diffusive limit. The subgap conductance in SN structures with barriers (zero bias and finite bias anomalies) are discussed. We also analyze the temperature dependence of the conductance variation δS(T) for a Andreev interferometer. We show that besides the well know low temperature maximum a second maximum near Tc may appear. We present the results of studies on the Josephson effect in 4-terminal SNS contacts and on the possible sign reversal of the Josephson critical current.