This trial is designed to compare the effects of twice-daily (before lunch and before dinner) exenatide plus oral antidiabetic (OAD) agents and twice-daily (before breakfast and before dinner) exenatide plus OAD with respect to glycemic control (HbA1c) in patients with type 2 diabetes.

Inclusion Criteria:

• Diagnosed with type 2 diabetes.
• Have been treated with one of the following treatment regimens for at least three months prior to screening: *metformin alone; *sulfonylurea (SU) alone; *thiazolidinedione (TZD) alone; *a combination of metformin and SU; *a combination of metformin and TZD.
• HbA1c between 7.1% and 10.0%, inclusive.
• Body Mass Index (BMI) > 25 kg/m^2 and < 45 kg/m^2

Exclusion Criteria:

• Have participated in an interventional, medical, surgical, or pharmaceutical study (a study in which an experimental drug, medical, or surgical treatment was given) within 30 days prior to screening.
• Have characteristics contraindicating metformin, SU, or TZD use.
• Are receiving chronic (lasting longer than 2 weeks) systemic glucocorticoid therapy (excluding topical and inhaled preparations) or have received such therapy within 2 weeks immediately prior to screening.
• Have used any prescription drug to promote weight loss within 3 months prior to screening.
• Are currently treated (for greater than 2 consecutive weeks) with any of the following excluded medications: *insulin within 3 months prior to screening; *alpha-glucosidase inhibitors within 3 months prior to screening; *meglitinides within 3 months prior to screening; *drugs that directly affect gastrointestinal motility