Inclusion criteria:
- Must be at least 18 years of age,
- Fluent in Persian,
- Minimum education: Diploma,
- Having chronic insomnia disorder according to DSM5 diagnostic criteria,
- Having anxiety or depression disorders or both according to SCID-I,
- Having a stable drug dose for six months before starting treatment and not increasing the drug dose or starting a new drug during treatment
Exclusion criteria:
- Having psychosis, bipolar disorder, substance dependence or abuse,
- Being involved in other concurrent psychological treatments,
,- Having overt suicidal thoughts,
- Having a debilitating physical illness or serious medical condition