  Relying on a few lowest order perturbative calculations of anomalous
dimensions of gauge invariant operators built from holomorphic scalar fields
and an arbitrary number of covariant derivatives in maximally supersymmetric
gauge theory, we propose an all-loop generalization of the Baxter equation
which determines their spectrum. The equation does not take into account
wrapping effects and is thus asymptotic in character. We develop an asymptotic
expansion of the deformed Baxter equation for large values of the conformal
spin and derive an integral equation for the cusp anomalous dimension.
