This manuscript was prepared during 2009-2010, and covers the period of beam commissioning and initial power ramp-up of the Spallation Neutron Source accelerator from late 2006 through 2009. The manuscript was originally intended for publication, but was never submitted. At this point in time ( 2015) the material has generally been presented and published elsewhere, and is dated enough that it is no longer appropriate to submit it for journal publication. None-the-less, it serves as a useful comprehensive reference for the SNS accelerator commissioning, and as such has been formatted for an ORNL-TM. It should be emphasized that the material in this report has not been updated in this most recent formatting process. This report serves as a snapshot of the progress of the SNS accelerator commissioning and rampup as of 2009.