COB, but it was definitely a choice by me. I was approached by one org on campus, but I had an off feeling about them. Of course I knew nothing at the time about how informal recruitment was supposed to go or I might have done things differently. I researched all the sororities on campus, decided which one was right for me on a national level, and arranged to meet some of the members to see if the chapter would be a good fit. I had lunch with TPA85 and the woman who would later be my big. They were fabulous! I had a couple great meetings with the chapter as a whole before they voted me in--after they had already done the initial ceremony, but they held another one just for me. Which, by the way, was terrifying.
Thank God I didn't have to do any other rituals alone. I thought I was going to faint in front of the president.