By examining various approaches and techniques, this paper aims to help designers to create improved algorithms for communications over noisy channels with memory.By Achilleas Anastasopoulos, Member IEEE, Keith M. Chugg, Member IEEE, Giulio Colavolpe, Member IEEE, Gianluigi Ferrari, Member IEEE, and Riccardo Raheli, Member IEEE ABSTRACT | In this paper, we present an overview on the design of algorithms for iterative detection over channels with memory. The starting point for all the algorithms is the implementation of soft-input soft-ouput maximum a posteriori (MAP) symbol detection strategies for transmissions over channels encompassing unknown parameters, either stochastic or deterministic. The proposed solutions represent effective ways to reach this goal. The described algorithms are grouped into three categories: i) we first introduce algorithms for adaptive iterative detection, where the unknown channel parameters are explicitly estimated; ii) then, we consider finite-memory iterative detection algorithms, based on ad hoc truncation of the channel memory and often interpretable as based on an implicit estimation of the channel parameters; and iii) finally, we present a general detection-theoretic approach to derive optimal detection algorithms with polynomial complexity. A few illustrative numerical results are also presented.