The current study examined the association between leadership self-efficacy and the developmental leadership model. The purpose was to better understand how leadership training transfers to facets of developmental leadership. This was tested in a cross-sectional design with military commanders in the Swedish Armed Forces. The results show that the sub-domain of leader self-control efficacy (the cognitive and emotional ability to remain composure) did not predict developmental leadership, but that leader assertiveness efficacy (the ability to make rational decisions) predicted the two dimensions of the exemplary model, and inspiration and motivation in the developmental leadership model. One possibility is that leader self-control efficacy can be what enables the individual to function within an extreme context, but leader assertiveness efficacy can be what most determines the leadership performance within that context. The possibility for mediatory analyses in further research is discussed.