Inclusion Criteria:  Minimum age of 18 years Meets Diagnostic Assessment Research Tool (DART) screening criteria for a primary diagnosis of depression and reports being at least moderately depressed according to the PHQ-9 Sufficient language proficiency to understand the treatment materials written at grade 10 reading level Understands what TAiCBT and is open and interested to participating in a study using this treatment modality Is able to reliably access the internet, and has basic computer skills to navigate the internet using a web browser Willing to participate in a waitlist-control study and be followed for 12 months  Exclusion Criteria:  Suicidal intent or clinically significant suicidal ideation Clinically significant self-harm Active psychotic illness Currently participating in psychological treatment for depression and/or receiving evidence-based treatment (other than medication) for depression Clinically significant alcohol and/or other substance use including prescription and over the counter medication that would likely interfere with treatment Current or previous diagnosis of Borderline Personality Disorder Does not meet DART criteria for a primary diagnosis of depression Change in psychotropic medication within 3 weeks of treatment baseline