Imaging polarimetry is one of the most promising tools to map the structure of faint protoplanetary disks. In this contribution we discuss the feasibility of imaging polarimetry of protoplanetary disks and the usability to answer the scientific questions in the field. From the theoretical side we do this by simulations of disks of various geometries and dust properties. We model the expected signal and detailed predictions for current and upcoming imaging polarimeters. This way we can address the question what the diagnostic value of polarimetry is for the structure of the disk and the characteristics of the grains in it. We compare extremely fluffy aggregated grains and compact homogeneous grains and show that their expected signal is significantly different. In combination with infrared/mm observations this could allow us to obtain grain properties in addition to mapping of the disk geometry. From the observational side we address the issues by discussing some of the early results from the Extreme Polarimeter (ExPo). ExPo is a sensitive imaging polarimeter designed to be a pathfinding instrument for the large imaging polarimetry projects planned for the VLT and the ELT. Already it proves to be a pioneering instrument in the field of imaging polarimetry of circumstellar matter.