  X-ray polarimetry-timing is the characterization of rapid variability in the
X-ray polarization degree and angle. As for the case of spectral-timing, it
provides causal information valuable for reconstructing indirect maps of the
vicinity of compact objects. To call X-ray polarimetry-timing a young field is
somewhat of an understatement, given that the first X-ray mission truly capable
of enabling polarimetry-timing analyses has only just launched at the time of
writing. Now is therefore an exciting time for the field, in which we have
theoretical predictions and are eagerly awaiting data. This Chapter discusses
the theoretical expectations and also describes the data analysis techniques
that can be used.
