Iterative demapper. Demodulation and/or demapping of a signal (e.g., based on a constellation whose points have a corresponding mapping with associated labels) is performed such that each dimension is processed separately without accounting for influences from the other dimension. For example, the demapping process operates on each respective dimension separately and independently. In some instances, the processing operates iteratively, in that, information identified from processing one of the dimensions is employed in directing the processing in another of the dimensions. Such operation may be performed iteratively by updating/modified information associated with one or more of the dimensions as well. Moreover, decoding may operate in accordance with iterative demapping (e.g., error correction code (ECC) and/or forward error correction (FEC) code by which information bits are encoded) to make estimates of bits within a signal sequence, and those estimates may be used in a subsequent iteration of demapping.