ABSTRACT Low income women of childbearing age are at disproportionate risk for depressive syndromes and, despite the availability of efficacious interventions, often do not receive the treatment they need.(1,2) We developed Mom- Net, a remote, coach-facilitated, Internet-based intervention adapted from an empirically-supported cognitive behavioral treatment (CBT) for depression to address the needs of depressed mothers. Two randomized control trials(3,4) demonstrated Mom-Net to be highly effective in reducing depressive symptoms and improving parenting behavior and child adjustment. In the proposed project we seek to examine whether we can expand the reach of the Mom-Net intervention by implementing within the Head Start Environment. Moving Mom-Net into HS requires that we focus on implementation processes to understand how agencies would interact with the intervention in order to implement with effectiveness and sustainability. As well, it is important to offer agencies delivery approaches that can best meet their available internal resources. To address these issues, we propose using a hybrid type 2, Effectiveness-Implementation design(5) to compare two implementation approaches for the delivery of Mom-Net, one with its existing high-intensity coaching approach, and one making use of a low- intensity coaching, designed to provide supportive accountability, but not psychoeducational support. We propose to follow the Exploration, Preparation, Implementation, and Sustainment process model (EPIS(6,7)) to guide the evaluation. The proposed study is predicated on: (a) HS's awareness of the need to identify and respond to maternal depression(8); (b) calls to embed maternal depression treatment into early childhood service settings(9-11); and (c) evidence of the effectiveness of web-based CBT approaches, guided by interventionists without formal mental health training(12,13). We will (a) examine characteristics of HS agencies related to each phase of the EPIS implementation model; (b) examine effectiveness (Maternal Depression; Parenting Behavior; Child Emotional and Behavioral Functioning) and implementation (reach, acceptability, fidelity, and cost) outcomes within a design in which agencies will be randomized to implementation approach, and mothers will be randomized, within agency, to either Mom-Net or Treatment as Usual (TAU)/waitlist conditions; and (c) finally, examine for each implementation strategy, the mediating influence of changes in maternal functioning associated with core Mom-Net skills on maternal depressive symptoms.