The purpose of this study is to examine the effects of neurocognitive enhancement on cognitive abilities and related social and adaptive behaviours in individuals diagnosed with major depressive disorder. Subjects in this study will be randomized to receive Neurocognitive Enhancement Therapy (NET) or to a wait list and then NET . Secondary aims include examining whether the cognitive benefits are potentiated by repeated exposure during in-home practice with complementary exercises. Additionally, the investigators will examine the durability of the effects and their generalization to functional capacity and everyday functional performance after completion of the groups.

Inclusion Criteria:

1. Male or Female.
2. Subjects will be between the ages of 18 and 65, which is the age range with available normative comparison data.

Exclusion Criteria:

1. Presence of a medical diagnosis that is associated with known cognitive impairments, such as multiple sclerosis, cerebrovascular accident, dementia, or history of traumatic brain injury.
2. Subjects with a reading level below grade 6, as assessed with the Wide Range Achievement Test - Reading Recognition Subtest, will be excluded because of the likelihood of not understanding task instructions.
3. Subjects with uncorrectable vision or hearing impairment that would preclude valid assessments or intervention procedures.