  It is well known that if the dimension of the Sasaki cone is greater than
one, then all Sasakian structures are either positive or indefinite. We discuss
the phenomenon of type changing within a fixed Sasaki cone. Assuming henceforth
that the dimension of the Sasaki cone is greater than one, there are three
possibilities, either all elements are positive, all are indefinite, or both
positive and indefinite Sasakian structures occur. We illustrate by examples
how the type can change as we move in the Sasaki cone. If there exists a
Sasakian structure in the cone whose total transverse scalar curvature is
non-positive, then all elements of the Sasaki cone are indefinite. Furthermore,
we prove that if the first Chern class is a torsion class or represented by a
positive definite (1,1) form, then all elements of the Sasaki cone are
positive.
