This report describes and evaluates the methods and procedures used in the 2004/09 Beginning Postsecondary Students Longitudinal Study (BPS:04/09). BPS:04/09 is the second and final follow-up interview for the cohort of first-time beginning postsecondary students identified in the 2004 National Postsecondary Student Aid Study. For the first time in BPS, in addition to the student interview, transcripts were collected from all of the postsecondary institutions attended by the sample. Together, the student interview and transcript data collections represent a significant and rich data source on this cohort of first-time beginning students. Appended are: (1) NPSAS:04 Institution and Student Sampling Details; (2) Technical Review Panel; (3) Data Elements for Student Interview; (4) Facsimile of Full-scale Instrument; (5) Training Material for Interviewers; (6) Notification Materials for Student Interview Data Collection; (7) Training Agendas for Transcript Data Collection; (8) Notification Materials for Transcript Data Collection; (9) Data Elements for Keying and Coding System; (10) Item Response Rates and Imputation Results; (11) Analysis Variables; (12) Design Effects; and (13) Nonresponse Bias Analysis.