To provide a realistic overview of a family of XSAPT methods, we divide this discussion into several parts. Section 2.1.1 compares different XC functionals used in SAPT0(KS) and SAPT(KS) methods. This choice has important consequences for accuracy and some poor choices can be found in the literature, which should not be emulated. Basis-set demands are discussed in Section 2.1.2 and because they are relatively forgiving (by ab initio standards), calculations can be performed in systems composed of large monomers. This capability is illustrated with examples in Section 2.1.3. Finally, Section 2.1.4 provides an overview of XSAPT for ions, which is one place where there is certainly room for future improvement.