The purpose of this study is to examine the extent to which delivering sleep and circadian focused interventions in addition to evidenced based psychiatric care for depression and suicide risk may contribute to decreasing suicide risk among high risk young adults. Investigators will evaluate three interventions targeting sleep in acutely suicidal college students enrolled in intensive outpatient treatment. Participants will be randomly assigned to one of three intervention groups:

1. Triple Chronotherapy (TCT)+ Transdiagnostic Sleep and Circadian Intervention (TSC)
2. Transdiagnostic Sleep and Circadian Intervention (TSC)
3. Sleep Feedback (SF) Participants will be followed for 6 months with primary outcome domains of suicidal thoughts and behaviors and depression evaluated by blinded clinicians at short (Days 1-4 of intervention), medium (2 months) and long (6 month) term intervals.

Suicide is currently the second leading cause of death among college students, and suicidal thoughts and behaviors (STBs) in this group have increased substantially in recent years. Indeed, young adulthood represents a particularly high-risk period for onset of psychiatric disorders associated with STBs, including depression, anxiety, and substance use disorder. There is a pressing need for efficacious treatments for suicidal college students that yield fast-acting and sustained effects in order to minimize disruption to young adults' developmental trajectories. While efficacious treatments exist to decrease suicide risk, effects generally take months. Interventions that rapidly improve suicidality are thus urgently needed. Triple chronotherapy (TCT) is a candidate, as two open studies documented dramatic reductions in suicidality. TCT is a 4-5 day intervention that involves one day and night of sleep deprivation, followed by 4 nights of sleep advance of bed/waketimes combined with morning bright light therapy (presumed to both advance the circadian rhythm and improve mood). Randomized control trials indicate that TCT rapidly improves depression, though suicide-specific randomized control trials have not been conducted to date. The investigators will thus propose to examine TCT as a means to rapidly reduce suicidality, but to also pair this with a multidimensional sleep health intervention (i.e., the Transdiagnostic Sleep and Circadian Intervention, TSC) to test whether this will help sustain improvements. Investigators assert that a "TCT+" package that includes TCT (4-day protocol) followed by TSC+ (6-8 outpatient sessions) holds promise to safely and non-invasively yield rapid and sustained improvement in depression and STBs among suicidal college students. This study is a 3-arm RCT comparing TCT+ vs TSC+ Alone vs Sleep Feedback (Ctrl) in 90 acutely suicidal college students, ages 18-25 years, reporting sleep difficulties and receiving Intensive Outpatient Program (IOP) treatment. The investigators will examine trajectories of depression and suicidality over short- (i.e., 4 days), medium- (i.e., 2 months), and long-term (i.e., 6 months).

Inclusion Criteria:

• Enrolled or planning to enroll in treatment at COSTAR Intensive Outpatient Program
• English language fluency and literacy sufficient to engage in study protocol
• Suicidal ideation or suicide attempt in past month
• Clinically significant sleep disturbance, operationalized as Pittsburgh Sleep Quality Index global PSQI score >= 7, and/or delayed bedtimes (>midnight), and/or >2 hours in sleep timing variability

Exclusion Criteria:

• Non-affective psychosis per electronic health record (EHR) review and/or baseline clinical assessment, or symptom severity or psychosocial functioning impairments that preclude participation
• Contraindications for either sleep deprivation or bright light therapy (e.g., bipolar disorder; seizure disorder; photosensitizing medication)
• Intellectual disability precluding comprehension of study procedures
• Evidence of untreated obstructive sleep apnea and/or restless legs syndrome
• Life-threatening medical condition requiring immediate treatment (such as cancer; end stage disease)
• Pregnancy