Based on personal experiences in conducting intensive ethnographic fieldwork, the social, emotional, and personal aspects of fieldwork that are often neglected in the literature are considered. The fieldwork involved observations within five diverse secondary schools during a 2-year period in conjunction with a project on microcomputer implementation in pre-college mathematics. The five stages through which the fieldwork progressed are described: (1) entry; (2) passive observation (classroom observations and analysis of documents, memos, and other secondary data); (3) active observation (interactions, interviews, summer workshop observations, and questionnaires); (4) participant observation (full participant observation, the evolving role of the investigator, and the impact of the researcher on the research site); and (5) exiting the field (planning to leave, disengagement, and responsibilities and obligations). Full participant observation complemented traditional data collection techniques of semi-structured interviews, conversations with key informants, distribution of questionnaires, and content analysis of relevant texts. Immersion in the field was achieved when the author obtained a position as a substitute teacher in one of the school districts involved. It is contended that decisions that direct the course of data collection inevitably depend upon more than detached scientific methodology. Hence, social, personal, and emotional factors affect each phase of the research process. By highlighting how the ethnographer's role evolved through these five stages and by critically examining how these changing roles affect the ethnographer's relationship to the data, this paper shows the need for a reflexive ethnography of educational settings. A 40-item list of references is included. (RLC)