GexPxS1−2x glasses in the compositional range have been synthesized and examined in temperature modulated differential scanningcalorimetry (MDSC) and Raman scattering experiments. Trends in the non-reversing enthalpyΔHnr(x) nearTg show the term toalmost vanish in the 0.090(5)<x<0.135(5) range, and to increase by an order of magnitude atx<0.09, andat x>0.135. In analogy to previous results on chalcogenide glasses, we identify compositions atx<0.09 to be elasticallyfloppy, those in the 0.090<x<0.135 range to be in the intermediate phase, and those atx>0.135 to be stressed rigid. MDSC results also show that theΔHnr term ages in the stressed-rigid and floppy phases but not in the intermediate phase.The intermediate phase is viewed to be a self-organized phase of a disorderednetwork. It consists of at least four isostatically rigid local structures: corner-sharingGeS4, edge-sharingGeS2, pyramidalP(S1/2)3 andquasi-tetrahedral S = P(S1/2)3 units for which evidence comes from Raman scattering. The latter method also shows the existenceof P4S7 and P4S10 molecules in the glasses segregated from the backbone. These aspects of structurecontribute to an intermediate phase that is significantly narrower in width than in thecorresponding selenide glasses.