This study compares the postulational approach to tenth grade geometry by three textbooks: one synthetic, one transformational, and one vectional. The development of incidence, order, distance, separation, congruence, parallelism, and similarity are discussed, and the different approaches illustrated. Special consideration is given to theorems in the transformation and vector approaches that have traditionally been postulates in synthetic geometry. It is found that the synthetic and transformation texts essentially differ only in the presentation of congruence and similarity, whereas the synthetic and vector texts are more noticeably different. Both the transformation and vector approaches emphasize function as a unifying concept, while all three texts hold the teaching of the deductive method as a primary objective. Also included is a section on methods of proof. (Author/MM)