The bottleneck of the wavefunction-based SAPT is a calculation of the triples dispersion correction, which scales as N 7 with the system size. Hohenstein and Sherrill demonstrated how to reduce that cost by appropriately truncating the virtual space, and a similar algorithm can be applied to the present theory. One possible way for dealing with σ operators with an excitation rank greater than 2 are tensor decomposition algorithms. Recently several works reported the reduction of the scaling of high-order coupled-cluster methods. The application to the dispersion operator σ in CCPP can be designed in the same way, as for example, for T 3 or T 4 , except that σ operator has lower symmetry related to the index permutation.