  Bilocal holography provides a constructive approach to the vector
model/higher spin gravity duality. It has two ingredients: a change of field
variables and a change of space time coordinates. The change of field variables
ensures that the loop expansion parameter becomes ${1\over N}$. The change of
coordinates solves the Clebsch-Gordan problem of moving from the tensor product
basis (in which the collective bilocal field is written) to the direct sum
basis (appropriate for the description of the gravity fields). We argue that
the change of space time coordinates can be deduced by requiring that operators
constructed in the bilocal collective field theory are dual to local operators
in the AdS bulk.
