Purpose: Diabetes mellitus (DM) is a growing problem in the United States and worldwide. Diabetes possesses a significant burden on the healthcare costs. An evidence-based, practical, and economically feasible strategy to tackle the growing burden of DM is imminent. Diabetes self-management education and support (DSMES) is the backbone to improve the care in DM. A research study called a nurse-led inpatient DSMES was designed and implemented in a community hospital on the west coast to improve patient knowledge of DM and medication adherence with DM. Methods: A descriptive, pretest-posttest study was employed to evaluate the effects of a DSMES program on patient knowledge of DM and patient medication adherence in an inpatient setting on the West coast. Convenience sampling was utilized, and the sample included 10 participants. Paired t-test was used to compare the group means before and after the provision of DSMES to the same sample. Results: The study revealed a statistically significant improvement (p = 0.026) in the participants' knowledge of DM after the provision of DSMES while no changes (although not statistically significant, p = 1.00), in the participants' medication adherence. Conclusions: Provision of DSMES by nurses can improve the outcomes of patients with DM in inpatient settings. Recommendations: Implementation of a nurse-led DSMES project has the potential to improve patient knowledge and diabetes self-management skills, which can, in turn, improve treatment adherence and potentially prevent frequent hospitalizations in patients with DM. Further large-scale studies are needed to generate further evidence to support the provision of DSMES by nurses.