Required Professional Development Units (PDUs): Are needed to maintain a teaching license for the state of Oregon. PDUs are determined by the amount of credits a teacher is getting from a graduate or non-graduate course at a university. All educators who have obtained a final license type will soon be required to complete Professional Development Units (PDUs) to renew, regardless of employment status. A “final license type” is defined as a license that an educator could choose to renew indefinitely, for the remainder of a career. This State of Oregon change takes effect January 1st, 2013.