Field trips, camps, and courses are considered a critical experience in the education of future geoscientists. Traditional bedrock geologic mapping continues to play a prominent role in field courses and a robust body of research describes how students gain content, skills, habits of mind, social engagement, and identity as a geologist in field settings. However, little work has examined instructional practices that lead to meaningful learning of geologic mapping. During a semi-structured interview, we asked 67 novice to professional geologists to reflect on how and where they learned geologic mapping. When analyzed through the lens of situated learning theory (Lave and Wenger 1991), responses from these geologists shed light on best practices for mapping instruction in field settings. Our findings highlight two contrasting forms of instruction and the importance of a community of practice. In structured instruction, students and instructors worked together through a prescribed learning progression. Conversely, in ill-structured instruction participants described receiving little guidance on how to progress. Overall, our participants reflected positively on learning experiences that built upon sufficient prior knowledge, allowed for some struggle but included generous instructor support, and provided the opportunity to work collaboratively with other learners. Our participants found regular feedback to be highly beneficial. We suggest that appropriate activities and assessments that encourage both teamwork (collaboration) and independent studies should be incorporated into field instruction. Additionally, the results of our study suggest that the community of practice is a crucial contributor to learning to map and that the learning is defined as much by the professional domain shared between novices and experts as it is by the physical domain provided by the complex Earth environment. In order for a learner to be authentically involved in the actual practice of an expert, the learner must work with and learn from the community of practice.