The present study conceptualized, implemented, and evaluated a specific program, the Live Science program. This program integrated 2 distinct but complementary approaches: participants' immersion in real science contexts and the participation of future teachers in seminars intended to share the immersion experience and to reflect on nature of science (NOS). Four future teachers participated in the Live Science program in 2 real research contexts. Through an analysis of the experiences and lessons learned from this program, this study tried to understand to what extent participation in real-context scientific activities, focused on an explicit and reflective approach to NOS, can contribute to the professional development of preservice elementary teachers. Interviews, questionnaires, observations, diaries, and videotaped seminars were used for data collection. Our findings suggest that the adoption of an explicit approach through illustration and reflection on particular aspects of NOS within the context of scientific research is a promising approach considering that it potentially allows for the development of a more informed understanding of science. The results also suggest that along with personality-related factors, the inherent characteristics of real science contexts play an important role in the development of that understanding. Tightly organized research teams capable of giving ample support to preservice teachers and working in research fields in which participants' conceptions can be confronted should be selected in order to improve the impact of this type of program.