Following a brief introduction, the chapter presents letters from doctoral researchers to a doctoral advisor, in which questions addressing several challenging data collection scenarios are posed. The letters are inspired by the author’s own experiences as a doctoral student and professor, as well as drawing from conversations and collaborations with other doctoral students, colleagues, advisors, and mentors. Intended to cover the entire data collection process, the letters begin with recruiting participants and continue to decisions about how to manage collected data. The letters are organized into three sections that approximate stages before, during, and after data collection: recruitment and project design; data collection; and data management. At the end of the chapter, four data collection lessons are provided, concerning all three stages of the data collection process.