Medical training is a lengthy procedure and involves an undergraduate education, medical school and graduate medical education. Most medical students will spend 4 years at a college or university to earn a BS or BA degree in basic sciences such as biology, chemistry and physics. Four years of education takes place at a US medical school, followed by a residency program that is 3-7 years depending on the medical specialty chosen. For additional training to become highly specialized in a particular field, 1-3 years of additional subspecialty training can be chosen by students. A physician must then obtain a license to practice medicine from a state or jurisdiction of the US in which they are planning to practice.