This report delves into the complexities of mental health nursing, examining the emotional, psychological, and social well-being of individuals. It presents three case studies, each exploring biopsychosocial factors contributing to mental health issues such as depression and schizophrenia. The report analyzes biological, psychological, and social influences, highlighting the importance of a comprehensive assessment model. It further details individual interventions tailored to each case, emphasizing the significance of ethical and legal considerations in nursing practice, including autonomy, beneficence, non-maleficence, and justice. The report concludes with a discussion on the importance of early diagnosis, appropriate treatment, and adherence to ethical principles to ensure effective patient care and overall well-being, underscoring the role of healthcare professionals in upholding legal and ethical standards within the Australian healthcare system.