Introduction Protection from ultraviolet (UV) radiation is considered the cornerstone of any cosmetic treatment plan, as sunlight directly affects pigmentation and skin aging. Mechanism of Sun Damage Ultraviolet radiation causes: • Activation of melanocytes → pigmentation • DNA damage in cells • Production of free radicals • Breakdown of collagen Types of Sunscreens Physical Sunscreens Reflect UV rays (e.g., Zinc oxide) Chemical Sunscreens Absorb UV rays and convert them into heat Proper Use • Reapply every 2–3 hours • Use an adequate amount • Apply 15–20 minutes before sun exposure Importance in Aesthetics • Prevents treatment failure • Reduces pigmentation • Maintains results of laser treatments Conclusion Sunscreen is not an option but an essential medical necessity. Prepared by: Asst. Lecturer Hussein Safaa Abdulameer Al-Mustaqbal University – The First University in Iraq