The Danish pseudopartitive constructions differ in their possibilities of definiteness marking: the Indirect Partitive Construction (IPC) (D N1 P N2) permits N1 to bear the definite suffix, while the Direct Partitive Construction (DPC) (D N1 N2) does not; in addition, neither construction permits the prenominal definite article in the absence of a prenominal modifier. Drawing on previous work regarding the morphosyntax of definiteness marking in Danish, we use the distribution of definiteness marking as a probe to illuminate the structure of the pseudopartitive constructions. Our conclusion is that despite superficial similarities the two constructions are quite different in structure, the IPC having a lexical N head and a PP complement, and the DPC a functional n head with an NP complement, forming a single extended projection of N2. These assumptions allow us to account for a number of differences in the behavior of these constructions, shedding light on the nature of pseudopartitives as well as on the theory of extended projections.