Veterans who are unemployed and living with mental health or substance use conditions are in need of integrative interventions that support their career development, mental wellness, and sobriety. However, career development interventions are often developed and implemented separate from mental health services. This paper introduces a novel intervention that supports career development of veterans with mental health and substance use concerns: Purposeful Pathways. This paper presents the results from three phases of intervention development: (1) retreats with clinical and vocational psychology experts (n=13) to develop the theoretical mechanisms of Purposeful Pathways, (2) focus groups with Veterans Health Affairs vocational counselors (n=6) who provide employment services to veterans with mental health conditions, and (3) an open trial in which veterans with mental health conditions (n=10) received Purposeful Pathways and provided feedback. Descriptions of the iterative processes of developing the Purposeful Pathways intervention are presented as a model for developing vocational interventions.