|Abstract:||This paper deals with the two main truncation processes that occur in Spanish. Type-A and Type-B hypocoristics represent two different degrees of Emergence of the Unmarked. Whereas Type-A hypocoristics achieve unmarkedness at the prosodic level only (e.g. a minimal prosodic word), Type-B hypocoristics further achieve unmarkedness at the segmental level (e.g. onset and nucleus optimization). Spanish hypocoristics are equivalent to a MinWd because they must contain no more than a single binary foot. When the Source Form exceeds this limit, some of the segmental material may not be preserved. In Type-A hypocoristics faithfulness to the initial part of SF is enforced by the constraints ANCHOR-L and I-CONTIGUITY, whereas in Type-B hypocoristics faithfulness to the head of the PWd is secured by HEAD(PWd)MAX. Type-B truncated forms display an additional tendency towards unmarkedness by favoring CV-syllables with optimal peaks and margins. In addition to causing the deletion of certain segments, this tendency towards greater unmarkedness yields the selection of low-sonority segments to fill the syllable onset and high-sonority segments to fill the nucleus. There are also certain sound substitutions that take place in Type-B hypocoristics (e.g. [c&] < [s], [p] < [f], [k] < [x], [l] < [r]). These are analyzed as a way to optimize the syllable by parsing segments that are more harmonic with the onset position.