This project contributes to a better understanding of the grammar underlying Spanish-English(-Kriol) codeswitching (CS). Its objective is threefold. First, at an empirical level, it provides insight into the way the conflict between synthetic/morphological and analytic/lexical patterns is handled in CS contexts. It therefore looks into the factors governing intensification (e.g. ‘a huge project’) and attenuation (‘a little lucky’), which express a quantitative or qualitative upward or downward scaling of a referent, and are very differently represented in Spanish, English and Kriol. Despite its common occurrence and varied forms, no research has as yet examined these patterns in a CS context. Second, the project aims at revealing the abstract or context-dependent nature of CS. It therefore observes how the conflict points are administered by multilingual speakers in three communities (Miami and El Paso in the USA, and Belize) that differ in geographical setting, history, and social status of the languages. Third, it wants to tackle the fragmented knowledge of the nature of CS by developing an integrative theory and assimilating insights from sociolinguistics, structural linguistics, and experimental psycholinguistics. Hence the project adopts a multimethod approach and combines the study of unexplored naturalistic data with an experimental design.