The paper examines anxiety as an important emotion for language learning and communication, using the intraindividual, dynamic emotional experience as a grounding for understanding the antecedents and consequences of anxiety arousal. The bulk of the existing literature, as reflected in three recent meta-analyses, treats language anxiety as a stable individual difference (ID) factor, documenting its correlations with test performance, course grades, and other indices of language proficiency. This literature contributes to understanding the impact of language anxiety on various linguistic processes. However, the typical ID approach has difficulty documenting the inner workings of language anxiety, and especially its dynamic relationships with other emotions, language processing, and the ebb and flow of anxiety in social situations. To address the limitations of the typical ID approach, this paper will argue that starting from an intrapersonal and dynamic perspective allows more detailed consideration of the myriad ways anxiety interacts with language, situating it among other influential processes that unfold in real time, including the complex interactions among positive and negative emotions. The paper will draw on the work emerging from the perspective of complex dynamic systems, with a focus on the value of individual-level methods for generating new types of research questions. The idiodynamic approach to research will be used to document the complexity of language anxiety in practice. The paper concludes with a call for more individual-level, highly contextualized research to document the inner workings of anxiety within individuals.