|Abstract:||Few previous research studies have investigated the decision processes that engineering students use when they transition from undergraduate programs to either professional practice or graduate programs. This study aims to describe how advanced engineering students decide their post-baccalaureate plans. Specifically, this study examines the factors that influence students’ choices: people, courses, projects, industrial internships, research experiences, etc. A mixed-methods study was conducted with engineering students at a large public university in the Midwest. A survey was administered to all 2293 seniors in engineering, and a similar survey was administered to all 664 first-year graduate students in engineering. The distribution of academic programs of the 62 seniors and 43 first-year graduate students who responded to surveys was similar to that of the entire populations. In addition, four seniors and four first-year graduate students were chosen for individual one-hour interviews. The eight students included men and women, and domestic and international students, across a range of engineering fields. According to the surveys, there were no statistically significant differences between men and women in their choices of post-baccalaureate plans. Students who had had positive undergraduate research experiences were more likely to enter graduate school immediately after graduation. Students who had had positive industrial internships were more likely to enter professional practice immediately. According to the interviews, some students seemed to drift into graduate school without clear goals or connections with their professional identities. Some entered graduate school because they were unable to find other appropriate employment. Some students chose professional practice because they had had negative undergraduate research experiences. Although students generally reported that they had made their post-baccalaureate decisions themselves, in reality, they appeared to be strongly influenced by people and prior experiences, particularly by the quality of any undergraduate research experiences.