  This paper investigates the space of codimension zero embeddings of a
Poincare duality space in a disk. One of our main results exhibits a tower that
interpolates from the space of Poincare immersions to a certain space of
"unlinked" Poincare embeddings. The layers of this tower are described in terms
of the coefficient spectra of the identity appearing in Goodwillie's homotopy
functor calculus. We also answer a question posed to us by Sylvain Cappell. The
appendix proposes a conjectural relationship between our tower and the manifold
calculus tower for the smooth embedding space.
