1. Defining treatment-resistant depression, difficult-to-treat depression, and staging treatment intensity 2. Clinical and epidemiological predictors of treatment-resistant depression 3. The economic burden of treatment-resistant depression: Cost-of-illness perspective 4. The neurobiology of treatmentresistant depression 5. Modeling treatment-resistant depression in the preclinical setting 6. Treatment algorithms for treatment-resistant depression 7. Tools to aid precision treatments to prevent or manage treatmentresistant depression (TRD): Pharmacogenomics, machine learning, and artificial intelligence 8. Tricyclic antidepressants for treatment-resistant depression 9. Monoamine oxidase inhibitors for treatment-resistant depression 10. Switching antidepressants in patients with treatment-resistant depression 11. Adjunctive strategies for treatment-resistant depression 12. Combining antidepressants to address treatment-resistant depression 13. Ketamine/esketamine for treatment-resistant depression 14. Psychedelic agents for treatmentresistant depression 15. Inflammation and treatment resistance: Mechanisms and treatment implications 16. Opioid agents for treatmentresistant depression 17. Transcranial magnetic stimulation for treatment-resistant depression 18. tDCS for treatment-resistant depression 19. ECT for treatment-resistant depression 20. MST for treatment-resistant depression 21. VNS for treatment-resistant depression 22. Deep brain stimulation for treatment-resistant depression 23. Other neurosurgical interventions for treatment-resistant depression 24. Treatment-resistant psychotic depression 25. Evidence-based psychotherapy for treatment-resistant depression 26. Treatment-resistant bipolar depression 27. Treatment-resistant depression in child and adolescents 28. Treatment-resistant depression in geriatrics 29. Identification and management of anxious depression in patients with treatment-resistant depression 30. Managing treatment-resistant depression with comorbid personality disorders 31. Managing treatment-resistant depression with comorbid substance use disorders 32. Managing treatment-resistant depression in the setting of chronic pain 33. Inhaled gases for treatmentresistant major depression 34. Drugs under investigation for treatment-resistant depression 35. Chronotherapeutics for treatmentresistant depression 36. Managing treatment resistant depression in primary care settings 37. Treatment-resistant depression in pregnancy, the postpartum period, and transition to menopause 38. Lifestyle interventions for treatment-resistant depression 39. Managing the risk of suicide in people with treatment-resistant depression 40. Maintaining motivation and preserving the therapeutic alliance as tools to overcome treatmentresistant depression