A great deal of research in health care has examined a wide range of variables to better understand the degree to which patients follow the advice of medical professionals in managing their health, known as adherence. This paper explains the development of the linguistic systems to describe and evaluate two psychosocial constructs (i.e. control orientation and agency) that have been found to be related to adherence in previous research for subjects with diabetes (Trento et al. 2007; Wangberg 2007; O'Hea et al. 2009). The present data came from 43 semi-structured in-depth interviews of subjects with Type 2 diabetes. One-on-one interviews with open-ended questions elicited subjects' 'stories' about living with diabetes, and the transcribed interviews were analyzed to develop the linguistic systems of control orientation and agency. The resultant systems were applied to the 43 interviews by raters with high inter-rater reliability. The results showed demarcations of clearly identified codings of patient types. The paper presents the linguistic coding systems developed in the study, the results of their application to the patient interview data, and recommendations for improved communication with patients.