Sacrae Theologiae Doctor (S.T.D.) (Doctor of Sacred Theology) (formerly Sacrae Theologiae Professor (S.T.P.), Professor of Sacred Theology), is the final theological degree in the pontifical university system of the Catholic Church. This compares with, for example in North American institutions, the four-year program for a B.A. at many universities, a two-year program for an M.A., and the writing and successful defense of the doctoral dissertation for the Ph.D. or Th.D. (an additional 2–3 years).