This study consisted of a longitudinal investigation into the information behavior of people diagnosed with a particular chronic serious health condition, type 2 diabetes. This study sought to identify the factors that motivate or impede the information seeking and use of these individuals and to discover how these factors and their influences change across time. It also aimed to uncover how they become aware of and capable of articulating their information needs, how they look for and make use of health-related information, and how these processes change across time. Lastly, it sought to discover what sources and types of diabetes-related information they perceive to be useful and how their perceptions of usefulness change as their knowledge about, and their experience with, diabetes transform across time. A longitudinal, mixed method approach was taken in which data were collected through two interview sessions spaced approximately four to six months apart. These sessions explored the experiences of 34 adults with type 2 diabetes, using a combination of qualitative and quantitative data collection techniques, including semi-structured interview, background questionnaires, health condition questionnaires, card-sorting exercises, and timeline elicitation. Both qualitative and quantitative techniques were used to analyze the data. The findings from this study provide evidence that information behavior plays a very important role in enabling participants to physically, cognitively, and affectively cope with having diabetes. Participants who rated diabetes-related information as more useful rated their general health higher and indicated that they felt less confused, more optimistic, and more in control of their experience with diabetes. This study's findings also show that time forms a critical dimension within the context of consumer health information behavior. Participants' information seeking and use practices, as well as their perceptions regarding the usefulness of diabetes-related information, also underwent important transformations across time. Moreover, their willingness and ability to act on this information also varied. Participants were not always immediately aware of their information needs and this state, termed "incognizance" here, sometimes led to serious health consequences. Having information at the point in time when it could be of the most use to them was of paramount importance. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://www.proquest.com/en-US/products/dissertations/individuals.shtml.]