A process for intra-operatively providing anatomical guidance in a surgery, comprising: (a) illuminating human tissues in an area of a human being in operation with a beam of light; (b) obtaining fluorescence data from light emitted from the human tissues in response to the illumination having a predefined wavelength, wherein the beam of light has a wavelength in the near-infrared range, and the fluorescence data comprises near-infrared auto-fluorescence data; wherein the process further comprises: (c) displaying images generated from the obtained near-infrared-auto-fluorescence data in a display (418; 438; 438a) for providing anatomical guidance to a medical professional performing the surgery, wherein the obtained near-infrared auto-fluorescence data comprises near-infrared auto-fluorescence intensity, and the displayed image is generated based on the near-infrared auto-fluorescence intensity; characterized in that the surgery is an endocrine surgery and the area of the human being is the neck area of the human being; wherein the predefined wavelength is selected such that the thyroid and the parathyroid, when illuminated by the beam of light, auto-fluoresce at 822 nm; and wherein the anatomical guidance is visualization of different tissue types in the neck area, to differentiate between the parathyroid and the thyroid and other tissue, wherein the near-infrared auto-fluorescence data are obtained in a wavelength range including the wavelength of 822 nm. (a) illuminating human tissues in an area of a human being in operation with a beam of light; (b) obtaining fluorescence data from light emitted from the human tissues in response to the illumination having a predefined wavelength, wherein the beam of light has a wavelength in the near-infrared range, and the fluorescence data comprises near-infrared auto-fluorescence data; the beam of light has a wavelength in the near-infrared range, and the fluorescence data comprises near-infrared auto-fluorescence data; (c) displaying images generated from the obtained near-infrared-auto-fluorescence data in a display (418; 438; 438a) for providing anatomical guidance to a medical professional performing the surgery, wherein the obtained near-infrared auto-fluorescence data comprises near-infrared auto-fluorescence intensity, and the displayed image is generated based on the near-infrared auto-fluorescence intensity; characterized in that the surgery is an endocrine surgery and the area of the human being is the neck area of the human being; wherein the predefined wavelength is selected such that the thyroid and the parathyroid, when illuminated by the beam of light, auto-fluoresce at 822 nm; and wherein the anatomical guidance is visualization of different tissue types in the neck area, to differentiate between the parathyroid and the thyroid and other tissue, wherein the near-infrared auto-fluorescence data are obtained in a wavelength range including the wavelength of 822 nm. wherein the obtained near-infrared auto-fluorescence data comprises near-infrared auto-fluorescence intensity, and the displayed image is generated based on the near-infrared auto-fluorescence intensity; characterized in that the surgery is an endocrine surgery and the area of the human being is the neck area of the human being; wherein the predefined wavelength is selected such that the thyroid and the parathyroid, when illuminated by the beam of light, auto-fluoresce at 822 nm; and wherein the anatomical guidance is visualization of different tissue types in the neck area, to differentiate between the parathyroid and the thyroid and other tissue, wherein the near-infrared auto-fluorescence data are obtained in a wavelength range including the wavelength of 822 nm.