Undergraduates may enroll for a three- or four-year program in engineering. Students choose a major when they enter the university, and cannot change it unless they opt later for the university's professional or self-financed postgraduate programs. Science and business disciplines are in high demand, largely in anticipation of better employment prospects. Most programs are organized on an annual basis, though some programs are semester dependent. Most departments offer masters programs of a year or a few years' duration. Research is conducted in specialized institutes as well as individual departments, many of which have doctoral programs.