Introduction: Practicing emergency medicine (EM) involves rapid decision-making in an acute setting, broad knowledge and a strong ability to multi-task. Some medical students find these characteristics attractive, while others find them a deterrent. Previous studies have indicated the range of characteristics that interest undergraduate students. No studies have followed students to assess how attitudes towards EM careers evolve over their schooling. Methods: An open-ended survey of medical students’ career interests was distributed at five data-collection points over the four years of undergraduate training from 1999-2006 at Memorial University. Guided by principles of grounded theory the qualitative data was coded to identify key themes and sentinel quotes. Semi-structured interviews with academic emergency physicians at Dalhousie University were then conducted to assess the relevance of these findings to postgraduate training (in progress). These transcripts were analyzed in the same manner as the longitudinal surveys. Results: 1281 surveys were completed by 540 students, with 758 comments about EM. The biggest drawbacks of EM included lack of patient follow-up and lack of experience in EM; the biggest benefits included variety of cases and patients, congruence with previous life experiences, and elective experiences. One major theme was the Certificant of the College of Family Physicians (CCFP) EM training, as it meant a shorter residency that was more transferrable to rural settings. Lifestyle was a prominent theme, seen as positive by some and negative by others. Emergency physicians commented on students’ naivety, especially relating to media and the nature of the work early in their training. Conclusion: Medical students’ opinions of EM tend to shift throughout their schooling, in particular, the perception of the work. Medical students’ perceptions differ significantly from that of experienced emergency physicians, highlighting the need for a greater degree of mentoring. Perceptions of lifestyle in EM are highly variable amongst students, acting as both a benefit and a drawback. Medical schools may be able to improve clinical exposure and provide more informed career counselling with respect to emergency medicine. Residency program directors can consider these findings during recruitment and interviewing to determine whether students have a realistic view of the specialty and career trajectory.