Nursing is the protection, promotion, and optimization of health through direct patient care, illness prevention, and advocacy. It is the largest healthcare profession in the United States, with roughly 3.4 million registered nurses working across hospitals, clinics, schools, homes, and community settings. Far more than bedside assistance, nursing spans a structured discipline with its own diagnostic framework, levels of practice, and specialized fields.
Core Purpose of the Profession
The American Nurses Association defines nursing as the protection and optimization of health and abilities, the prevention of illness and injury, the facilitation of healing, and the alleviation of suffering. That last piece is important: nurses don’t just carry out medical orders. They diagnose and treat “human responses” to illness, meaning they focus on how a health problem affects a whole person, not just the disease itself.
Virginia Henderson, one of the most influential nursing theorists, put it more simply. She described the nurse’s unique role as helping individuals, whether sick or well, perform activities that contribute to health or recovery that they would do on their own if they had the strength, will, or knowledge. That captures the spirit of the work: nursing fills the gap between what patients need and what they can do for themselves.
How Nurses Think: The Nursing Process
Nursing care follows a five-step framework that guides every clinical decision. It’s sometimes called ADPIE, after its steps: assessment, diagnosis, planning, implementation, and evaluation.
- Assessment. The nurse collects both subjective data (what the patient says about how they feel) and objective data (measurable things like vital signs, weight, and fluid intake).
- Diagnosis. Unlike a medical diagnosis that names a disease, a nursing diagnosis identifies the patient’s response to a health problem. For example, a medical diagnosis might be pneumonia, while the nursing diagnosis focuses on impaired breathing or anxiety related to the illness.
- Planning. The nurse sets specific, patient-centered goals and outlines interventions to reach them.
- Implementation. This is the action step, where the nurse carries out the care plan.
- Evaluation. After intervening, the nurse reassesses the patient to determine whether the goals were met or the plan needs to change.
This cycle repeats continuously. A nurse doesn’t assess once and move on. Every shift, every patient interaction feeds new information back into the process.
Levels of Nursing Practice
Nursing isn’t a single role. It’s a profession with distinct tiers, each with different education requirements, responsibilities, and levels of independence.
Licensed Practical Nurse (LPN)
LPNs complete about one year of training at a hospital, community college, or technical school, then pass the NCLEX-PN licensing exam. They provide basic patient care, often in long-term care facilities and home health settings. LPNs generally work under the supervision of a registered nurse, advanced practice nurse, or physician. In some states they can supervise certified nursing assistants.
Registered Nurse (RN)
Becoming an RN requires more education, though there are several paths. A diploma program through a hospital takes about two years. An associate degree in nursing (ADN) typically takes two to three years at a community college. A bachelor of science in nursing (BSN) takes four years at a university. All three routes lead to the same licensing exam, the NCLEX-RN, but a BSN opens more doors for advancement and is increasingly preferred by employers.
RNs assess, monitor, and treat patients. They supervise LPNs and nursing assistants, educate patients and families, coordinate care across teams, and serve as advocates when patients can’t speak for themselves.
Advanced Practice Registered Nurse (APRN)
APRNs hold a master’s or doctoral degree and have specialized clinical training. This category includes nurse practitioners, nurse anesthetists, and nurse midwives. They often lead care teams and, depending on the state, can diagnose conditions, prescribe medications, and practice independently without physician oversight. A doctorate in nursing (either a PhD or a Doctor of Nursing Practice) is the highest level of education in the field.
Specialty Areas
Within each level, nurses can specialize. The range is enormous. Nurse practitioners alone practice in areas such as adult and geriatric acute care, primary care for families, pediatrics, and midwifery. Beyond nurse practitioner roles, nurses work in emergency departments, operating rooms, intensive care units, psychiatric facilities, public health agencies, schools, and research labs. Some focus on leadership and health systems analytics. Others specialize in forensic nursing, informatics, or palliative care. The breadth of the profession means that two nurses with the same license can have day-to-day jobs that look nothing alike.
Philosophical Foundations
Nursing has a rich theoretical tradition that shapes how care is taught and practiced. Florence Nightingale, widely considered the founder of modern nursing, developed her environmental theory during the Crimean War in the 1850s. She observed that clean air, pure water, proper drainage, and good nutrition dramatically affected patient outcomes. Her book, “Notes on Nursing: What It Is, and What It Is Not,” remains a foundational text in nursing education.
Later theorists expanded the philosophy. Jean Watson’s theory of human caring argues that caring itself is a core, irreplaceable part of the profession, and that nurses must attend to the mental, physical, social, cultural, and spiritual dimensions of a patient’s environment. Faye Abdellah identified 21 distinct nursing problems that could be addressed through individualized care plans, pushing the field toward the person-centered approach that defines it today.
A common thread runs through all these frameworks: nursing treats people, not just conditions. The environment, the patient’s emotional state, their family, their goals for recovery all fall within the nurse’s scope of concern.
Evidence-Based Practice
Modern nursing relies on evidence-based practice, a systematic approach that blends three things: the best available research evidence, the nurse’s own clinical expertise, and the individual patient’s needs and preferences. This means a nurse doesn’t simply follow tradition or intuition. When deciding how to manage a patient’s pain or prevent a wound infection, they draw on current research, adapt it to the specific clinical setting, and tailor it to what that particular patient values and can realistically do.
Licensing and Regulation
Every nurse in the United States must pass a national licensing exam before practicing. LPNs take the NCLEX-PN, and RNs take the NCLEX-RN. Beyond the exam, each state’s board of nursing sets its own requirements for education, clinical hours, and scope of practice, which is why what a nurse can legally do varies from state to state.
Nursing programs must satisfy the educational requirements of the state where they’re located. For students enrolled in distance education programs after July 2024, the curriculum must also meet the requirements of the state where the student lives or intends to work. This means choosing an accredited program that aligns with the state you plan to practice in matters more than ever.
Job Outlook and Demand
The Bureau of Labor Statistics projects that registered nurse employment will grow 5 percent from 2024 to 2034, faster than the average for all occupations. That translates to roughly 166,000 new positions, bringing the total to about 3.56 million RNs by 2034. Demand is driven by an aging population, increasing rates of chronic disease, and the expanding role of nurses in primary and preventive care. Nursing consistently ranks among the most in-demand healthcare professions in the country.