Аннотация:For every quasirational (pro-p) relation module R, we construct the so called p-adic rationalization, which is the pro-fd module. We show how it embeds into a sequence which arises from a certain prounipotent crossed module. The latter can be seen as concrete examples of proalgebraic homotopy types. We provide the Identity Theorem for pro-p-groups, answering a question of Serre.