Half a century onward, this essay reflects on a field project initiated in 1963 that examined the human use and vertical distribution of wild, weedy, and cultivated species between 4314 m and 700 m in the Urubamba (or Vilcanota) Valley, southern Peru. Five well-defined climatic zones from microthermal to macrothermal characterize that valley, which was inhabited by a then largely non-literate Quechua-speaking peasantry. Direct observation, interviewing, plant collecting, and mapping characterized the 18-month effort to retrieve the tacit knowledge held by rural people and to convert that information into formal knowledge for others to read. Obstacles peculiar to the period had to be surmounted and shortcomings of various kinds overcome. That first big research endeavor, an intense and intensive learning experience, imparted a sense of intellectual autonomy in selecting topics; respect for the power of intrinsic motivation; a view of fieldwork as a source of adventure; and a perspective on ethnobiology as a form of delicate empiricism that is not simply a matter of registering an objective world. Retrospection on ethnobiological fieldwork at the dissertation stage provides another way to examine the circumstances of knowledge creation and its transformative possibilities.