This presentation will discuss a 14-year ethnographic research project investigating the cognitive practices that have been leading to scientific discoveries in four bioengineering sciences labs, two in biomedical engineering that conduct experiments with physical simulation models (tissue engineering and neural engineering)and two in integrative systems biology labs (one that does only computational modeling in collaboration with bioscientists and the other that does modeling and conducts bench top experiments to further their modeling). My research group conducted open interviews, field observations of the researchers at work, and collected various archival data, including draft and published papers, research proposals to funding agencies, records of lab meetings, power point presentations prepared for various purposes, and dissertation proposals. I began this line of research out of the conviction that 1) philosophers should not cede studies of science labs to sociology of science since these are also cognitively rich domains and 2) much of what goes on in scientific discovery practice that is relevant for philosophical analysis is not preserved for the historical record. I will discuss significant insights into discovery and problem solving – around topics of philosophical interest such as method development, modeling and simulation, concept formation and change, and explanation – that could only have been gleaned from data of the day-to-day research processes that the ethnographic interviews and observations provide. This kind of research also has significant potential for making philosophy of science relevant to and collaborative with scientists in facilitating their research agendas. As an emerging interdisciplinary fields these areas face many challenges such as how to organize research labs, how to facilitate cross-disciplinary collaborations, and how to train researchers. I will discuss how our investigations have been providing bioengineering researchers with insights into these challenges.