We study the relation between Nominal Logic and the Theory of Contexts, two approaches for specifying and reasoning about datatypes with binders. We consider a natural-deduction style proof system for intuitionistic nominal logic, called NINL, inspired by a sequent proof system recently proposed by J. Cheney. We present a translation of terms, formulas and judgments of NINL, into terms and propositions of CIC, via a weak HOAS encoding. It turns out that the (translation of the) axioms and rules of NINL are derivable in CIC extended with the Theory of Contexts (CIC/ToC), and that in the latter we can prove also sequents which are not derivable in NINL. Thus, CIC/ToC can be seen as a strict extension of NINL. Copyright © 2005 ACM.