Students who have obtained a bachelor’s degree can continue their education by pursuing one of two types of degrees. The first is a master’s degree. This is usually a two-year degree that is highly specialized in a specific field. Students are sometimes admitted to a master’s degree program only if they have a bachelor’s degree in a closely related field. However, there are many exceptions to this, such as with students who want to pursue a Master’s in Business Administration (MBA) degree. Students who want to advance their education even further in a specific field can pursue a doctorate degree, also called a PhD. A PhD degree can take between three and six years to complete, depending on the course of study chosen, the ability of the student, and the thesis that the student has selected. The thesis is a very intensive research paper that must be completed prior to earning the degree. It is always required of students pursuing a PhD, and may sometimes be required of students pursuing a master’s degree (depending on the school).