The aim of this paper is to introduce the astrological texts which circulated under the name of Ptolemy in the Latin tradition. About twenty such texts are known at present, two of which stand out as the most popular among all the works attributed to Ptolemy: the (authentic) Quadripartitum and the (spurious) Centiloquium. The former was translated into Latin at least nine times between 1138 (Plato of Tivoli) and 1553 (Philipp Melanchthon), and the latter at least seven times between Adelard of Bath in the 1120s (?) and 1477 (Giovanni Pontano).