Although some critics consider it time-consuming and demanding, proponents of the monolingual approach for field research (i.e., learning to speak a target field language as part of the research process) argue that it can provide a unique insight into its structures. However, this claim remains largely unsubstantiated in the available literature on field methods. The present paper sets out to achieve a twofold objective: First, it reviews prior observations about the monolingual method in documentary-linguistics publications, highlighting important gaps in research. Secondly, based on qualitative data from the author's fieldwork context in rural, indigenous China, it contributes to addressing one such gap by demonstrating how, when, and why basic to intermediate communicative competence can enhance the documentation, description, and analysis of a field language, in ways that complement and sometimes outperform other approaches such as bilingual and stimuli-based elicitation.