Chris, Brian, and I often get asked "what is the difference between a residency and a fellowship program?" I am going to answer this question from an orthopedic perspective so please feel free to add your own perspective if you come from a different background. When talking with students about residency and fellowship programs, I often relate the question to the medical school model. Generally, medical students enter a residency program following medical school. A residency is a post-professional planned learned experience in a specific field of interest. For example, students interested in Orthopedics pursue Orthopedic surgery residencies. Following a medical residency, doctors have the opportunity to pursue a fellowship program. Using the example above, an Orthopedic Surgeon may choose to enter a hand surgery fellowship. Each step of learning further specializes the candidate. The process is similar for physical therapists.
Following graduation, physical therapists have the opportunity to enroll in residencies. These programs are generally one year long and prepare students for their specialty certification. For example, Chris and I completed an Orthopedic Residency and were able to sit for our Orthopedic Clinical Specialty (OCS). Brian completed a Sports Residency and sat for his Sports Clinical Specialty (SCS). Other residency programs exist for the many other specialties of physical therapy- geriatrics, pediatrics, cardiopulmonary to name a few. The residency teaches you to be a clinical expert.
Following residency, I chose to enter a fellowship in manual therapy. To enter a fellowship program, one must either complete a residency program, be a clinical specialist, or complete a year of pre-fellowship coursework. Pre-fellowship coursework can be obtained in several ways. (For example, Chris and I recently paired with OPTIM to start a COMT program. Our COMT program gives candidates the opportunity to pursue a manual therapy fellowship if they choose.) Fellowship training is not appropriate for new physical therapy graduates so the pre-fellowship year is a method of preparing students for fellowship training. It is the most advanced clinical certification a physical therapist can receive.
I hope this helps differentiate physical therapy residencies vs. fellowships. Let me know if you have further questions!