This chapter focusses on models of language production and the temporal organization of the processes involved in lexical access. Albert Costa contributed significantly to advancing our understanding of lexical access. Through the investigation of multilingual speakers, he added an important dimension to this discussion. Here, we provide a discussion of discrete and cascaded/interactive accounts of lexical access and summarize some of the crucial experimental evidence that has been offered for and against these different theories, roughly over the years when Albert contributed to these debates. We will also discuss whether or not lexical selection is competitive and what research on multilingual speech production contributed to our knowledge on lexical access. The discussion is mainly restricted to behavioral data, with some references to electrophysiological studies. We conclude that considering the experimental evidence a strict version of discrete processing models is difficult to maintain. Research on bilingual language production has made important contributions to the discussion, however, the picture is not yet complete.