A polarized view of Relativistic Accelerators: Pulsar Wind Nebulae in the IXPE era

Pulsars and Pulsar Wind Nebulae, are perhaps the most studied high-energy astrophysical systems, and constitute one of the most promising astrophysical environment where high energy processes and particle acceleration can be investigated. Moreover they are the only objects for which previous X-ray polarization has been reported. I will report on the objective of the IXPE mission for the study of PWNe, what are the main target of interest, what we hope to see and what are the preliminary results of their broad analysis, especially in the context of our present knowledge of how these systems work, and in the light of previous polarization measure both in X-ray and in other bands.