We study the adiabatic response of open systems governed by Lindblad evolutions (or Gorini-Kossakowski-Sudarshan) and hence affected by some form of friction. In particular, we present the analog of the Kubo formula for such systems. There is though an ambiguity in the definition of observables arising as fluxes (rates), such as velocities and currents. For a suitable notion of flux, the formulae for the transport coefficients are simple and explicit and are governed by the parallel transport on the manifold of instantaneous stationary states. Among our results we show that the response coefficients of open systems, whose stationary states are pure states, is given by the adiabatic curvature and may exhibit quantization, thus retaining features from the case without friction. Other notions of fluxes may lead to quantizations of inverse response coefficients, e.g. of resistances instead of conductances.