Inclusion Criteria:  English-speaking full-time professional firefighter At least 18 years of age A global Pittsburgh Sleep Quality Index score ≥ 5 (Grandner et al., 2006) Be willing and able to participate in all study activities including pre-, post-, and 3-month follow up assessments and 6-weeks of the CBT-I intervention Agree to random assignment to one of two conditions (treatment or control group) Have access to an email account Be willing to wear the Fitbit Inspire HR device throughout the duration of the intervention and for two weeks following completion of the 6-week intervention  Exclusion Criteria:  Endorsement of prior involvement in formal CBT-I interventions Unwillingness to give written informed consent