This paper deals with non-parallel realizations of NC clusters in Malay from the perspective of phonological positions and morphological affiliation of the NCs. It is argued that asymmetrical realizations of the Malay NCs stem from various combinations of phonological positions such as prominent onset position compared to coda position and morphological membership of the two elements belonging to prominent stem versus affix in the cluster. When a prefix-final nasal is followed by a voiceless obstruent, nasal substitution occurs. If the nasal is followed by a voiced obstruent, regressive place assimilation occurs but if the nasal is followed by a sonorant consonant, the prefix-final nasal is deleted. These processes do not apply to an NC̥ across the stem-suffix boundary. In prefix-prefix boundary, however, place assimilation only occurs when a nasal is followed by a voiceless obstruent. These various asymmetrical realizations of the Malay NCs are explained by constraints which reflect relativity of prominence of phonological positions and morphological affiliations of the NCs.