Recent years have witnessed a shift in empirical investigations of language learners' willingness to communicate (WTC) from quantitative studies examining the ways in which WTC antecedents co-act and contribute to communication, treating the concept as a stable characteristic, to a mixed-methods approach that allows the examination of stable behavioral tendencies and dynamic changes brought about by contextual variables. The rationale behind this study comes from the assumption that more profound understanding of motives underlying learners' readiness or reluctance to speak may help create classroom conditions that facilitate communication, thus contributing to linguistic attainment. More specifically, the study represents an attempt to tap factors that shape advanced learners' WTC during conversation classes in four different groups of students. Each time, the data were collected by means of self-ratings (i.e. indications of the level of WTC on a scale from -10 to +10) and immediate reports (i.e. questionnaires including closed and open-ended items). A combination of quantitative and qualitative analysis revealed that the extent to which WTC fluctuated was impacted by a range of contextual and individual factors. It was enhanced in particular when students were given the opportunity to communicate with familiar receivers in small groups or pairs on topics related to personal experiences.