The assessment of patients with severe Acquired Brain Injury (sABI) is mandatory in every phase and setting of care, and requires a multidimensional and interdisciplinary approach, to develop the individual rehabilitation project, and monitor long-term functional outcomes. In 2001 the Italian Society of Physical and Rehabilitation Medicine (SIMFER) published the minimal assessment protocol for traumatic sABI, providing a comprehensive, standardized functional assessment based on the International Classification of Functioning, Disability and Health (ICF), 2001. In 2007, a new protocol was published, extended to all sABI patients (PMGCA). In 2019, the SIMFER appointed a working group to provide a revised, updated version: the PMGCA2020. The purpose of this study was to describe the minimal assessment protocol to be applied at every stage and setting of the care process of patients with sABI. The working group, including one neurologist and 11 physiatrists experts in sABI rehabilitation, performed a review of the international recommendations for sABI assessment focusing on the following key words: "sABI assessment," "sABI rehabilitation," "sABI prognostic factors," "sABI rehabilitation assessment," "sABI outcome," in MEDLINE. Revision and integration proposals by each member were written and motivated, discussed and voted. The PMGCA2020 is addressed to sABI adult patients. It investigates the main clinical problems of sABI at any time of the rehabilitation pathway. It includes a demographic/anamnestic section, a clinical/functional assessment section and an outcome measures section following the ICF model of functioning and the model of the construction of the rehabilitation project. The PMGCA2020 provides an updated tool for the multidimensional rehabilitation assessment of sABI patients, at any stage of the rehabilitation pathway. Further studies will allow the validation of this minimum set of variables paving the way to an assessment standardization of patients with sABI in the rehabilitation settings. This minimum set of variables, defining patient's functioning and clinical status and outcomes, at every stage and setting of the care process to provide a framework for the standardization of the clinical evaluation of patients with sABI in rehabilitation settings.