The paper addresses the problem of maximizing information flow in a wireless network with a single source, a single destination, and an arbitrary number of relay nodes. The authors propose a deterministic channel model that captures key wireless properties such as signal strength, broadcast, and superposition. They provide an exact characterization of the capacity of networks with nodes connected by such deterministic channels, generalizing the max-flow min-cut theorem for wired networks. Using insights from the deterministic analysis, they design a new quantize-map-and-forward scheme for Gaussian networks. This scheme quantizes the received signal at the noise level, maps it to a random Gaussian codeword, and forwards it to the destination. The authors show that this scheme can achieve the cut-set upper bound within a gap that is independent of the channel parameters, specifically 1 bit/s/Hz for single-relay and two-relay Gaussian diamond networks. The scheme is universal, meaning relays do not need knowledge of channel parameters to achieve the rate supportable by the network. The paper also discusses extensions to multicast, half-duplex, and ergodic networks.The paper addresses the problem of maximizing information flow in a wireless network with a single source, a single destination, and an arbitrary number of relay nodes. The authors propose a deterministic channel model that captures key wireless properties such as signal strength, broadcast, and superposition. They provide an exact characterization of the capacity of networks with nodes connected by such deterministic channels, generalizing the max-flow min-cut theorem for wired networks. Using insights from the deterministic analysis, they design a new quantize-map-and-forward scheme for Gaussian networks. This scheme quantizes the received signal at the noise level, maps it to a random Gaussian codeword, and forwards it to the destination. The authors show that this scheme can achieve the cut-set upper bound within a gap that is independent of the channel parameters, specifically 1 bit/s/Hz for single-relay and two-relay Gaussian diamond networks. The scheme is universal, meaning relays do not need knowledge of channel parameters to achieve the rate supportable by the network. The paper also discusses extensions to multicast, half-duplex, and ergodic networks.