An analytical method is proposed to synthesize the angle-dependent surface susceptibilities, χ of spatially dispersive or non-local zero-thickness metasurfaces. The proposed method is based on the extended Generalized Sheet Transition Conditions (GSTCs), whereby spatially dispersive metasurfaces are modeled using angle-dependent surface susceptibilities that take the form of rational polynomial functions of the transverse wave-vector, k∥. The suggested method derives the rational polynomial form of χ(k∥), which can then be expressed in the space-domain using spatial derivatives of the fields, resulting in a corresponding higher-order spatial boundary condition to achieve the desired field operation. The proposed synthesis method is illustrated using variety of examples such as, a space-plate, spatial filters and field absorbers, which are then validated using an Integral Equation (IE) solver, in which the corresponding higher-order boundary conditions are integrated to predict the scattered fields. The proposed method thus not only represents a simple way to synthesize ideal zero-thickness metasurfaces, but helps establishes a way to define fundamental operational limits of spatially dis- persive metasurfaces. This is illustrated by considering the space- plate example, and deriving the fundamental trade-off between operation bandwidth and the achievable space-compression.