ABSTRACT Approximately 130,000 foot ulcer related amputations are performed each year in the US, costing about 100 billion dollars annually and at great impact to the quality of life of diabetic patients. Pressure-reducing footwear aimed at preventing ulcers is the main preventive measure, but it has been shown to be only meagerly effective. There exists a great need for more effective preventive footwear, which can only be developed through a better understanding of ulceration pathomechanics. This longitudinal study will be conducted on a cohort of patients with diabetic neuropathy and a prior ulcer history over an estimated mean of 12 months. Using state-of-the-art equipment, two primary ulcer-causing factors will be quantified every month over the follow-up period; plantar shear and temperature, along with pressure and physical activity. The purpose of this study is to identify more accurate markers and/or marker combinations for foot ulceration. Investigators will also analyze time trajectories of the four factors to identify potential trends towards ulceration. The uniqueness of the study is due to employment of a novel device capable of measuring 3D foot stresses and its longitudinal design with multiple measurements over time. Recent studies have shown the significance of plantar shear stresses in ulceration. This study will explore a longitudinal association between the locations of shear stresses and ulceration for the first time. Variations in foot temperature and potential relevance to ulceration will be revealed. Identifying and understanding reliable ulceration markers could lead to revolutionary preventative measures including development of footwear that monitors and minimizes ulceration risks.