In the context of language instruction and learning, L2 willingness to communicate (WTC) is a relevant factor in learners’ language use. It is viewed as a volitional process influenced by individual, social, linguistic, and situationally dependent factors. Foundational research focuses on either trait or state WTC-influencing factors as separate entities. Current research considers the dynamic relationship that occurs between the two though less research exists on how WTC manifests in classroom interaction. This study investigates such differences by examining learners’ self-reported, perceived trait WTC and situational state WTC. It treats WTC as a dynamic entity which is shaped by learners’ investment in language learning and the identity they take on as language learners. It considers the relationship of WTC to its three most influential trait variables: motivation, L2 perceived competence, and L2 anxiety. It presents findings of additional variables influencing state WTC. Data were comprised of questionnaire surveys, focal participant interviews, and classroom observations. Quantitative data consisted of 39 participants, and qualitative data consisted of 12 focal participants. The importance of the present study lies in its investigation of WTC in relation to trait and state factors, and its stance that investment in L2 learning is a key factor in fostering classroom WTC. Finally, it explores how WTC can be positively fostered to optimize the learner’s language experience. / Spanish