This report provides a comprehensive overview of Alzheimer's disease, including its aetiology, pathophysiology, diagnostic techniques, and treatment options. The aetiology section discusses the role of amyloid plaques and tau tangles in the brain, while the pathophysiology section details neuronal impairment and dysfunction in specific brain regions. Diagnostic techniques such as mental status tests, neuropsychological tests, and brain imaging (MRI, CT scan, PET scan) are described. The report also covers the use of cholinesterase inhibitors and memantine for treatment, as well as the management of behavioural symptoms. The references include key research papers on Alzheimer's disease, providing a strong foundation for understanding the disease and its management. The report also explores the stages of Alzheimer's disease and the symptoms associated with it, and the importance of early diagnosis and intervention.