This chapter provides a comprehensive guide to conducting participant observation within the field of professional training and development in an organizational behavior context. It offers a three-phase structured approach to understanding and navigating the complexities of fieldwork in such settings. The chapter begins by outlining the preparation phase, where researchers are guided on formulating research questions, developing a robust research design, and securing access to training sites. It then delves into the initial stage of fieldwork, focusing on immersion and exploration to capture the nuanced dynamics of professional training environments. Subsequent sections discuss the transition to the last phase of routine observations, emphasizing the importance of maintaining analytical reflexivity and adapting to evolving field conditions. Practical examples and guidelines are included to equip researchers with the tools needed for effective participant observation and to foster a deep understanding of professional training and development processes in organizational behavior research.