At two crucial junctures, Field has made use of metalogical results: (a) in his reformulation of the notion of conservativeness in nominalistically acceptable terms (Field 1989, pp. 119–120; Field 1991), and (b) in his nominalist proof of the conservativeness of set theory (Field 1992). These two outcomes are crucial for Field, since they establish the adequacy of conservativeness for the mathematical fictionalist. For (a) settles that the latter can formulate that notion without violating nominalism, and (b) concludes that conservativeness is a feature that mathematics actually has. But if these two outcomes are not legitimate, Field's approach cannot get off the ground. I will now consider whether these two uses of metalogical results are acceptable on nominalist grounds.