I consider the rule of assertion according to which knowledge is sufficient for epistemically proper assertion. I examine a counterexample to this rule recently proposed by Jennifer Lackey. I present three responses to this counterexample. The first two, I argue, highlight some flaws in the counterexample. But the third response fails. The lessons I draw from examining these three responses allow me to propose two counterexamples to the sufficiency rule that are similar to Lackey’s but avoid its problems.