This document discusses various phonological processes that occur at morpheme or word boundaries, known as sandhi. It defines internal and external sandhi and provides examples. Assimilation is introduced as a common process where one sound becomes more like an adjacent sound. The document discusses regressive and progressive assimilation and provides examples. It also discusses coarticulation, epenthesis, elision, linking/intrusive r, and differences between rhotic and non-rhotic accents of English. IPA transcriptions are provided for many of the examples discussed.