Resulting from a collaboration among three departments, the standard enthalpies of formation of some crystalline bis(8-hydroxyquinolate) metal complexes were determined by reaction-solution calorimetry. Enthalpies of hydrolysis were measured for several samples of each complex using various acidic solvents. 8-hydroxyquinoline is written as Hox. At 298.15 K, DELTA(f)H(m)- (M(ox)2,cr)/(kJ mol-1) values are : Mg(ox)2, -516.0 +/- 4.0; Ca(ox)2, -607.7 +/- 4.4; Sr(ox)2, - 585.9 +/- 4.1; Ba(ox)2, -573.4 +/- 4.5; Cu(ox)2, - 103.3 +/- 3.3; Zn(ox)2, - 271.5 +/- 3.6; Cd(ox)2, - 179.6 +/- 4.3; Pb(ox)2, - 145.3 +/- 3.8; Mn(ox)2, -307.1 +/- 3.7; Fe(ox)2, -219.7 +/- 4.5; Co(ox)2, -160.4 +/- 4.2; Ni(ox)2, - 165.5 +/- 5.6. Where feasible, standard enthalpies of sublimation at 298.15 K were determined by measuring vapour pressures as functions of temperature. DELTA(cr)gH(m)(-)(M(ox)2)/(kJ mol-1) values are : Mg(ox)2, 230.2 +/- 4.0; Cu(ox)2, 168.7 +/- 7.3; Zn(ox)2, 183.2 +/- 6.3; Cd(ox)2, 201.7 +/- 7.5; Pb(ox)2, 187.1 +/- 6.2; Mn(ox)2, 194.6 +/- 10.4; Co(ox)2, 205.3 +/- 4.0; Ni(ox)2, 175.4 +/- 6.7. From the standard enthalpies of formation in the gaseous state, the mean metal-ligand dissociation enthalpies were derived and compared with corresponding values for other complexes of these metals.