In addition to clinical practice, other activities encompassed in the physical therapy profession include research, education, consultation and administration. Definitions and licensing requirements in the United States vary among jurisdictions, as each state has enacted its own physical therapy practice act defining the profession within its jurisdiction, but the American Physical Therapy Association (APTA) has also drafted a model definition in order to limit this variation, and the APTA is also responsible for accrediting physical therapy education curricula throughout the United States of America. In many settings, physical therapy services may be provided alongside, or in conjunction with, other medical or rehabilitation services.
Physical therapy involves the interaction between physical therapist, patients/clients, other health care professionals, families, care givers, and communities in a process where movement potential is assessed and diagnosed and goals are agreed upon..  Physical therapy is performed by a physical therapist (PT) or physiotherapist (physio), and sometimes services are provided by a physical therapist assistant (PTA) acting under their direction.
In some cases, physical rehabilitation technicians may provide physiotherapy services. PTs are healthcare professionals who diagnose and treat individuals of all ages, from newborns to the very oldest, who have medical problems or other health-related conditions, illnesses, or injuries that limit their abilities to move and perform functional activities as well as they would like in their daily lives. PTs use an individual's history and physical examination to arrive at a diagnosis and establish a management plan and, when necessary, incorporate the results of laboratory and imaging studies. Electrodiagnostic testing (e.g., electromyograms and nerve conduction velocity testing) may also be of assistance. PT management commonly includes prescription of or assistance with specific exercises, manual therapy, education, manipulation and other interventions.
In addition, PTs work with individuals to prevent the loss of mobility before it occurs by developing fitness and wellness-oriented programs for healthier and more active lifestyles, providing services to individuals and populations to develop, maintain and restore maximum movement and functional ability throughout the lifespan. This includes providing services in circumstances where movement and function are threatened by aging, injury, disease or environmental factors. Functional movement is central to what it means to be healthy.