I investigate the phonetic realization of syllable structure in Chicano English (=ChE) to characterize its status as a language contact dialect, its relation to the target language, and the changes it undergoes. I study two simplification processes, one consonantal and one vocalic, in the vernacular of a balanced sample of forty-five adult Chicanos (=Mexican-Americans), non-native and native speakers, across five generations using methods of empirical linguistics. A well-studied sociolinguistic variable, /-t,d/ deletion, serves to linguistically situate ChE in the absence of a description of the matrix dialect. When compared to a cross-dialectal characterization of the variable, I find differences in ChE. I discover no cross-generational changes, or convergence in the constraints of /-t,d/ deletion (including non-native speaking immigrants); although one morphological change is attributed to differences in language use of two age-groups. Increased deletion is correlated both with: greater sonority in the preceding segment; and lower sonority in the following segment. I attribute the latter findings to specific aspects of English syllable structure. The less-studied variable, in sociolinguistic terms, is unstressed vowel reduction. Spanish, the substrate, has no vowel reduction while English does, so I investigate how ChE develops vowel reduction. Formant frequency measurements are made of stressed and unstressed vowels for four speakers. I find that Euro-American vowel reduction is not \u27acquired\u27 by ChE native speakers. Neither generation, language use at home, bilingualism versus monolingualism, or any linguistic factor plays a developmental role. Rather, a distinctive ChE pattern is found: mid vowels reduce while mid vowels do not reduce. When a fifth speaker is considered, a regular progression is tentatively suggested: vowel reduction develops in proportion to the amount of exposure to matrix dialect speakers. I did not consistently find native speaker resolution of interference-type confusions in speech of the non-native speaker. The dialect\u27s distinctive constraints on the simplification processes are shared by non-native and monolingual native speakers alike; generation is not significant. In a sense, the contact dialect establishes its characteristics before it has native speakers. Accommodation to the matrix dialect is an independent social process that involves the nature of contact between dialects