The present study explored the development of second language (L2) Chinese learners' ability to negotiate requests in interactions. It investigated the effect of proficiency on learners' use of request strategies and internal modifications and on their sequential realization of requests in L2 Chinese. Twenty-four American English learners of L2 Mandarin Chinese at three different proficiency levels completed a three-scenario role-play task. The scenarios were kept low in imposition and social distance but variable in power relations. Each participant interacted with a native speaker interlocutor who assumed different roles in those scenarios. Baseline data were provided by 10 native speakers (NSs) of Chinese. A total of 102 role-plays were coded for request strategies, internal modifications, and supportive moves, as well as the sequential placement of supportive moves in pre-, insert, and postexpansions. Situational variations as reflected in role-play production were considered alongside. The results showed that learners across proficiencies had the same range of pragmatic strategies as in NSs' repertoire, but they showed a general incompetence in employing internal modifications. Learners' ability to delay the requests improved with increasing proficiency, but learner production in general did not show the same level of situational variations as observed in the NS data.