Despite disparities in health problems and outcomes, people with disabilities are underrepresented in diabetes research. This results in a lack of evidence-based knowledge regarding best approaches in caring for this population. This article addresses the need for research that includes people with disabilities and describes the common reasons persons with disabilities are not included in research, including scientists' concerns regarding threats to a study's internal validity and cost. Arguments are provided as to how involving people with disabilities in research will improve our science and reduce disparities in this population. In addition to the ethical reasons for including persons with disabilities in research, the ability to generalize study findings to this population and thus speed our development and translation of this knowledge for use by clinicians is discussed. The bias in study conclusions that arise from study samples that do not include persons with disabilities and its possible effect on care delivery are presented. Two strategies that researchers can use to increase the inclusion of persons with disabilities in research are described: (1) Universal Design of Research and (2) intervention optimization study designs. Universal Design of Research includes research design processes such as the use of multisensory formats for recruiting participants, approaches to designing and presenting research instruments and interventions, and methods of data collection to promote the inclusion of participants with a wide range of abilities in research studies. Intervention optimization study designs offer an efficient way for scientists to rapidly build the most potent interventions for a wide range of people, including those with disabilities participating in mainstream research.