Abstract. In this talk, I will show how to isolate Effective Field Theory scattering amplitudes in the space of non-perturbative two-to-two amplitudes, using the S-matrix Bootstrap. We do so by introducing the notion of Effective Field Theory cutoff in the S-matrix Bootstrap approach. We perform a detailed comparison of the full unitarity bounds with those obtained using positivity and linearized unitarity, and discuss the notions of Spin-Zero and UV dominance along the boundary of the allowed amplitude space. Finally, we show that this construction also leads to novel bounds on operators of dimension less than or equal to six.