Power Corrections to TMD Factorization

In this paper we discuss calculation of power corrections to the transverse momentum dependent (TMD) factorization which describes production of a particle with small transverse momentum in a hadron-hadron collision. As an example we consider power corrections to the TMD factorization formula for Z-boson production. We demonstrate that in the leading order in N_c power corrections can be expressed in terms of leading-twist TMDs which is a consequence of QCD equations of motion.