Standard (p°) 0.1 MPa) massic energies of combustion for 2-piperidone, 1-methyl-2-piperidone, 1-benzyl-2piperidone, 1-methyl-4-piperidone, 1-ethyl-4-piperidone, and 1-benzyl-4-piperidone were measured at T ) 298.15 K by static bomb calorimetry. The standard molar enthalpies of formation in the condensed phase were derived. The standard molar enthalpies of vaporization at T ) 298.15 K of the piperidone and derivatives studied were determined by high-temperature Calvet microcalorimetry. The respective standard molar enthalpies of formation in the gaseous phase, at T ) 298.15 K, were derived. These results are discussed in terms of molecular structure contributions.