We present our clinical experience with two complex cases of deep fascial space infections of the neck. The first was a case of cervical necrotizing fasciitis involving the submental space. The second was an infection beginning at the soft palate and extending to the anterior mediastinum. Both infections emanated from an oral source in patients with diabetes mellitus, and both patients required multiple surgical debridements and endotracheal intubation for airway protection. Despite the declining incidence of deep space neck infections, our cases illustrate the challenging diagnostic and treatment dilemmas for the clinician managing patients with diabetes.