First-year MBS Ph.D. students select a total of 6 courses mini courses for the Spring semester (2 courses per block). Block 1 course codes are 621-625; Block 2 course codes are 626-630; Block 3 course codes are 631-636. MBS Ph.D. students in their second year and beyond, or CDB or MMG Master's students, register for the number of courses as needed.