Dao An (312/314-385) was one of the most prominent theorists in early Chinese translation history. His most popular teaching of wu shi san bu (五失 三不) has caused numerous debates since the Jin dynasty. To understand the debated issues, I examined all his sutra prefaces collected within the Collection of Records Concerning the Translation of Tripitaka (出三藏記集) in order of composition and came to a preliminary conclusion that Dao An’s thought could be periodized into an initial and a mature phase, and that the key to understanding the change in his thinking was the Translation Forum (譯場) in the capital city Chang-an (長安). Taking this previous study as an example, the present paper goes a step further into the Translation Forum to investigate the specific elements that might have caused the change in his thinking. According to my study, the Translation Forum produced not only Buddhist sutras but also early translation theories. In a sense, it was a cultural, religious and political institution in which Buddhism was transmitted, Buddhist sutras were translated, and translation discourses were negotiated. More importantly, this paper shows that, within this social institution, those who participated in the process of sutra translation, especially Zhao Zheng (趙政), the government official in charge of the Forum, and other participants, presumably the patrons of the Forum, had the tremendous power to decide which sutras would be translated and what translation strategies would be applied. Translation, according to André Lafevere, does not occur in a social vacuum. Similarly, discourses on translation and translation history cannot be detached from the specific contexts of translation production and use.