Thermodynamical properties of Kerr-Newman black holes are described in anti
-de Sitter space. Typical thermodynamic functions are derived in geometrica
l parameters. The black-hole solution is shown to exist at any finite tempe
rature and to satisfy the so-called Bekenstein-Hawking relation. Local stab
ility as well as the phase structure of the black-hole system is then exami
ned for the canonical ensemble. Global stability of the black-hole system i
s also discussed in proper reference to the value of angular velocity.