 A 12-week, randomized, double-blind, parallel-group, placebo-controlled acute phase trial of escitalopram is proposed in 222 persons with asthma and Major Depressive Disorder MDD. This sample will consist of 80 stratified into the High severity group which will consist of a baseline score or 20 on the 17-item Hamilton Rating Scale for Depression HRSD and or 3 courses of oral corticosteroids in the past 12 months. A separate group stratified into the Low severity group of 142 with MDD and asthma but HRSD-17 scores of 20 and 3 courses of oral corticosteroids in the past 12 months. A 16 week continuation phase is also proposed for depression responders at week 12. The participants will be recruited at the Parkland Hospital Health System PHHS Asthma and Allergy Clinics and Aston Clinic using the Self-Report Screening Tool for Depression 2-SRSD, a brief depression questionnaire, as part of routine clinical practice. Potential participants will be given an appointment scheduled at the PIs office to complete baseline assessment at which time written informed consent will be obtained before any study-specific assessments are completed. At the baseline appointment, the RA will administer the Structured Clinical Interview for DSM-IV SCID at baseline to establish a current diagnosis of MDD. Participants meeting all inclusion criteria will then be administered the IDS-SR30, the SF-36, the Asthma Control Questionnaire ACQ, Mini Asthma Quality of Life Questionnaire Mini AQLQ, the Cumulative Illness Rating Scale CIRS, the PRD-III Somatic Symptom Scale PRD-III for side effects, a blood draw for routine laboratory analyses, and forced expiratory volume in 1-second percentage of normal FEV1 will be assessed using a portable spirometer. Self-reported asthma-related emergency room visits and hospitalizations will be quantified for the past 12 months. 