We report on the eﬀect of interfacial energy on the glass temperature, Tg, of several amorphous polymers with various glass temperatures and polymer/substrate interactions conﬁned within self-ordered nanoporous alumina (AAO). The polymers studied include poly(phenylmethylsiloxane) (PMPS), poly(vinyl acetate) (PVAc), 1,4-polybutadiene (PB), oligostyrene (PS), and poly(dimethylsiloxane) (PDMS). The segmental dynamics and associated Tg’s are studied by means of dielectric spectroscopy. The interfacial energy for the polymer/substrate interface, γSL, is calculated with Young’s equation whereas the AAO membrane surface energy is obtained by measuring contact angles for several reference liquids. We ﬁnd that interfacial energy plays a signiﬁcant role in the segmental dynamics of polymers under conﬁnement within AAO. There is a trend for a decreasing glass temperature relative to the bulk with increasing interfacial energy. PDMS exhibits the highest interfacial energy and the highest reduction in glass temperature within AAO. Other eﬀects that may also contribute to changes in Tg are discussed.