I examine the radical contextualists’ two main arguments for the semantic underdeterminacy thesis, according to which all, or almost all, English sentences lack context-independent truth conditions. I show that both arguments are fallacious. The first argument, which I call the fallacy of the many understandings, mistakenly infers that a sentence S is semantically incomplete from the fact that S can be used to mean different things in different contexts. The second argument, which I call the open texture fallacy, wrongly concludes that a sentence S lacks context-independent truth conditions from the fact that there are circumstances in which the truth value of S would be indeterminate. I do however defend the claim that a certain class of sentences not containing any indexicals do lack context-independent truth conditions, and put forward an argument to that effect. But this argument, as I show, does not generalize to all sentences, and thus fails to support the semantic underdeterminacy thesis.