Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)We begin a study of a pro-p analogue of limit groups via extensions of centralizers and call L this new class of pro-p groups. We show that the pro-p groups of L have finite cohomological dimension, type FP(infinity) and non-positive Euler characteristic. Among the group theoretic properties it is proved that they are free-by-(torsion free nilpotent) and if non-abelian do not have a finitely generated non-trivial normal subgroup of infinite index. Furthermore it is shown that every 2 generated pro-p group in the class L is either free pro-p or abelian.26741671109128Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)