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The remarkable breadth of exoplanetary systems most likely finds its origin in their parent protoplanetary disks. Understanding the diversity of the physical properties and evolutionary pathways of these disks is therefore key to interpret the wealth of data that has been accumulated on exoplanets over the past two decades. High-angular resolution observations of disks comma the most direct method to characterize their properties comma is a challenging task in most cases and detailed individual studies are limited to a small set of favorable objects which are unlikely to be representative of the entire population. Edge-on protoplanetary disks offer unique advantages by blocking direct starlight and by providing an ideal perspective to study the disk vertical structure comma which is expected to be affected by dust settling as part of the planet formation process. After a few serendipitous early discoveries comma a method to identify likely edge-on disks was designed based on their peculiar spectral energy distribution. An HST pilot program confirmed that over half of the candidates were resolved as edge-on disks. Here we propose to conduct a complete survey of all HST-accessible edge-on disk candidates in four nearby star-forming regions (Taurus-Auriga comma Chamaeleon comma Lupus comma Ophiuchus) to confirm their nature comma and to enable a statistically meaningful ensemble analysis of the properties of protoplanetary disks. This survey is expected to roughly triple the number of edge-on disks identified through a uniform set of criteria in these regions and will allow us to empirically determine the true diversity of disk properties and to identify trends connected to disk evolution.