Stop guessing when to drink your last coffee. This practical digital ebook helps caffeine-sensitive professionals protect nighttime sleep without giving up the morning coffee they enjoy. Instead of relying on a generic cutoff that may not fit your schedule, you will map your real coffee routine, identify personal sensitivity signals, and follow a structured 14-day timing experiment. You will learn how dose, timing, bedtime, wake time, sleep onset, nighttime awakenings, and next-day alertness fit together so you can recognize a repeatable pattern rather than overreacting to one difficult night. Across six focused chapters, you will move from understanding your response to choosing a sustainable cutoff that works with real life. The ebook includes a Personal Caffeine Sensitivity Profile and a 14-Day Coffee and Sleep Tracking Log to help you record useful observations and make a clearer decision. Read it at your own pace, apply the process independently, and keep your morning coffee while building a more informed sleep-protective routine.