I investigate two accounts of modality that are united by their anchoring possibility and necessity in the objects of the actual world: essentialism and potentialism. According to essentialism, the necessary truths are those that are true in virtue of all objects taken together; according to potentialism, the possible truths are those that some things have potentials (dispositions, abilities, etc.) to make true. Essence relates to necessity much as potentiality relates to possibility, so it may be thought that the two accounts are ultimately equivalent. I argue that they are not, and further examine the relation between the notions of essence and potentiality, and their respective prospects in formulating an account of modality.