Critically ill patients require complex care in a technologically sophisticated environment where they are highly vulnerable to pressure-related injuries. However, pressure injury (PI) development remains a multifactorial phenomenon in critically ill persons; true risk is both pervasive and elusive. The purpose of this comprehensive review of the empirical literature was to examine the risk factors associated with PIs among adult patients admitted to contemporary intensive care units (ICUs). Inclusion criteria stipulated publications were to be peer-reviewed, quantitative studies with a focus on pressure ulcer (PU) risk factors in adult critical care patients published between 2010 and 2016 in which statistical analysis involved multivariate analysis using PU development as the outcome variable. Studies not available in English, those in which the primary focus was on PU prevention or treatment, and those that focused solely on the use of PU risk assessment scales were excluded. A comprehensive review of the OVID and PubMed computerized databases using the search terms pressure ulcer, critical care, intensive care, and risk factors yielded 540 reports; 358 remained after duplicates were eliminated and 28 after the inclusion/exclusion criteria were applied. Following examination, 16 studies were suitable for inclusion. A total of 43 risk factors emerged. Of those, 7 were identified in 3 or more studies in multivariate regression analysis; these included age, prolonged ICU admission, diabetes mellitus, cardiovascular disease, hypotension, prolonged mechanical ventilation, and vasopressor administration. To facilitate results interpretation, risk factors from multivariate analyses were grouped in 6 broad categories: demographic/patient characteristics, comorbidities, intrinsic factors, iatrogenic/care factors, PI risk assessment scales, and severity of illness/mortality risk. The shared attribute of the 7 risk factors identified was they are all potentially nonmodifiable. Advancing the science regarding the pathogenesis of PI development is imperative when trying to better understand unavoidable pressure-related injuries. The need for large multisite studies and studies using large datasets capable of validating risk factors unique to this population persists. Additionally, the need for enhanced PI risk quantification for adult ICU patients remains.