This study is designed to evaluate the effect on glycemic control when pioglitazone and metformin are taken together. Individuals participating in this study will provide written informed consent and will be required to commit to a screening visit and approximately 5 additional visits at the study center. Study participation is anticipated to be about 31 weeks (or approximately 8 months). Multiple procedures will occur at each visit which may include fasting, blood collection, urine collection, physical examinations and electrocardiograms.